Describe the bug

When cross-compiling with a sysroot, pkgconf will prepend the sysroot to all include and lib directories, even those of Conan packages, which is wrong since they are not under the sysroot (see #16468 ). If the .pc files have "-uninstalled" appended (e.g. somepackage-uninstalled.pc) then pkgconf's behavior is correct.

Note that PR #19229 can be reverted (adding sysroot property back in) after adding -uninstalled.

Note also it looks like there is an (incomplete?) PR #19303 which attempts to fix the same bug by using an env var instead of the -uninstalled postfix. I don't know which is the preferred/most correct approach.

How to reproduce it

No response