docs: cleanup warnings

[joshka]

warning: unexpected `cfg` condition name: `winapi`
   --> src/lib.rs:256:11
    |
256 | #[cfg(all(winapi, not(feature = "winapi")))]
    |           ^^^^^^
    |
    = help: expected names are: `clippy`, `debug_assertions`, `doc`, `docsrs`, `doctest`, `feature`, `miri`, `overflow_checks`, `panic`, `proc_macro`, `relocation_model`, `rustfmt`, `sanitize`, `sanitizer_cfi_generalize_pointers`, `sanitizer_cfi_normalize_integers`, `target_abi`, `target_arch`, `target_endian`, `target_env`, `target_family`, `target_feature`, `target_has_atomic`, `target_has_atomic_equal_alignment`, `target_has_atomic_load_store`, `target_os`, `target_pointer_width`, `target_thread_local`, `target_vendor`, `test`, `ub_checks`, `unix`, and `windows`
    = help: consider using a Cargo feature instead
    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
             [lints.rust]
             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(winapi)'] }
    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(winapi)");` to the top of the `build.rs`
    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration
    = note: `#[warn(unexpected_cfgs)]` on by default

warning: unexpected `cfg` condition value: `winapi`
   --> src/lib.rs:256:23
    |
256 | #[cfg(all(winapi, not(feature = "winapi")))]
    |                       ^^^^^^^^^^^^^^^^^^
    |
    = note: expected values for `feature` are: `bracketed-paste`, `default`, `event-stream`, `events`, `filedescriptor`, `libc`, `serde`, `use-dev-tty`, and `windows`
    = help: consider adding `winapi` as a feature in `Cargo.toml`
    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration

warning: unexpected `cfg` condition name: `crossterm_winapi`
   --> src/lib.rs:259:11
    |
259 | #[cfg(all(crossterm_winapi, not(feature = "crossterm_winapi")))]
    |           ^^^^^^^^^^^^^^^^
    |
    = help: consider using a Cargo feature instead
    = help: or consider adding in `Cargo.toml` the `check-cfg` lint config for the lint:
             [lints.rust]
             unexpected_cfgs = { level = "warn", check-cfg = ['cfg(crossterm_winapi)'] }
    = help: or consider adding `println!("cargo::rustc-check-cfg=cfg(crossterm_winapi)");` to the top of the `build.rs`
    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration

warning: unexpected `cfg` condition value: `crossterm_winapi`
   --> src/lib.rs:259:33
    |
259 | #[cfg(all(crossterm_winapi, not(feature = "crossterm_winapi")))]
    |                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: expected values for `feature` are: `bracketed-paste`, `default`, `event-stream`, `events`, `filedescriptor`, `libc`, `serde`, `use-dev-tty`, and `windows`
    = help: consider adding `crossterm_winapi` as a feature in `Cargo.toml`
    = note: see <https://doc.rust-lang.org/nightly/rustc/check-cfg/cargo-specifics.html> for more information about checking conditional configuration

warning: `crate::event::read` is both a function and a module
  --> src/cursor/sys/unix.rs:16:32
   |
16 | /// [`crossterm::event::read`](crate::event::read) or [`crossterm::event::poll`](crate::event::poll) are being...
   |                                ^^^^^^^^^^^^^^^^^^ ambiguous link
   |
   = note: `#[warn(rustdoc::broken_intra_doc_links)]` on by default
help: to link to the function, add parentheses
   |
16 | /// [`crossterm::event::read`](crate::event::read()) or [`crossterm::event::poll`](crate::event::poll) are being called.
   |                                                  ++
help: to link to the module, prefix with `mod@`
   |
16 | /// [`crossterm::event::read`](mod@crate::event::read) or [`crossterm::event::poll`](crate::event::poll) are being called.
   |                                ++++

warning: `crate::event::read` is both a function and a module
   --> src/terminal/sys/unix.rs:184:32
    |
184 | /// [`crossterm::event::read`](crate::event::read) or [`crossterm::event::poll`](crate::event::poll) are bein...
    |                                ^^^^^^^^^^^^^^^^^^ ambiguous link
    |
help: to link to the function, add parentheses
    |
184 | /// [`crossterm::event::read`](crate::event::read()) or [`crossterm::event::poll`](crate::event::poll) are being called.
    |                                                  ++
help: to link to the module, prefix with `mod@`
    |
184 | /// [`crossterm::event::read`](mod@crate::event::read) or [`crossterm::event::poll`](crate::event::poll) are being called.
    |                                ++++

warning: this URL is not a hyperlink
  --> src/style/types/colored.rs:74:31
   |
74 |     /// in environment as per https://no-color.org/
   |                               ^^^^^^^^^^^^^^^^^^^^^ help: use an automatic link instead: `<https://no-color.org/>`
   |
   = note: bare URLs are not automatically turned into clickable links
   = note: `#[warn(rustdoc::bare_urls)]` on by default

warning: this URL is not a hyperlink
   --> src/style.rs:187:34
    |
187 | /// crossterm supports NO_COLOR (https://no-color.org/) to disabled colored output.
    |                                  ^^^^^^^^^^^^^^^^^^^^^ help: use an automatic link instead: `<https://no-color.org/>`
    |
    = note: bare URLs are not automatically turned into clickable links

warning: this URL is not a hyperlink
   --> src/terminal.rs:151:15
    |
151 | /// For unix, https://man7.org/linux/man-pages/man4/tty_ioctl.4.html documents them as "unused".
    |               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use an automatic link instead: `<https://man7.org/linux/man-pages/man4/tty_ioctl.4.html>`
    |
    = note: bare URLs are not automatically turned into clickable links

warning: `crossterm` (lib doc) generated 9 warnings (run `cargo fix --lib -p crossterm` to apply 3 suggestions)
    Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.08s
   Generated /Users/joshka/local/crossterm/target/doc/crossterm/index.html

[joshka]

There is no winap / crossterm_winapi cfg constant, there is also no explicit feature for either of these. Both dependencies are included when the windows feature is enabled, so these lines are not possible to trigger and would be redundant anyway.