Dehybridized branch todo list

[brooksdavis]

Things to do:

• Jenkins support
• __CHERI_USER_ABI -> __CHERI__
• __CHERI_PURE_CAPABILITY__ -> __CHERI__
• reduce __has_feature(capabilities)?
• swap kernel defaults
• make lib64 purely legacy

Things to remove:

• kintcap_t
• kuintcap_t
• __kerncap
• __CHERI_USER_ABI
• __cheri_addr/__cheri_fromcap/__cheri_tocap/__cheri_offset
• __capability (kept ones in cheribsdtest, cheric.9, contrib, libprocstat)
• __DE*_CAP()
• __CHERI_HYBRID__
• hybrid support in lib/libsysdecode/utrace.c
• intcap_t
• *_c() in libc
• IOVEC_INIT_C