[extrowerk]

struct itimerval was bound but getitimer, setitimer and the
ITIMER_* constants were not. Add them, strptime, and the
CLOCK_VIRTUAL, CLOCK_HIGHRES and CLOCK_PROF clock ids that the
existing comment already mentions.

The C11/C23 timespec_get/timespec_getres and their TIME_* bases
are illumos additions (ILLUMOS_0.20/ILLUMOS_0.52) and go in the
illumos module.

sys/time.h: https://github.com/illumos/illumos-gate/blob/b56614870515295c253babb2b10fffdd3c60fdbe/usr/src/uts/common/sys/time.h#L199-L212
sys/time.h: https://github.com/illumos/illumos-gate/blob/b56614870515295c253babb2b10fffdd3c60fdbe/usr/src/uts/common/sys/time.h#L402-L410
sys/time_impl.h: https://github.com/illumos/illumos-gate/blob/b56614870515295c253babb2b10fffdd3c60fdbe/usr/src/uts/common/sys/time_impl.h#L120-L134
time.h: https://github.com/illumos/illumos-gate/blob/b56614870515295c253babb2b10fffdd3c60fdbe/usr/src/head/time.h#L105-L106
time.h: https://github.com/illumos/illumos-gate/blob/b56614870515295c253babb2b10fffdd3c60fdbe/usr/src/head/time.h#L306-L316

Testing

• cargo check for x86_64-unknown-illumos, aarch64-unknown-illumos,
  x86_64-pc-solaris and sparcv9-sun-solaris (with -Dwarnings).
• Every name in the applicable libc-test/semver lists compiles for
  illumos and Solaris; new constant values were cross-checked
  mechanically against the illumos-gate headers.
• ci/style.py checks (rustfmt, sorted/unique semver lists, style test).
• CC=clang cargo test -p libc-test on OmniOS r151060 (x86_64): passes

@rustbot label stable-nominated

🤖 Generated with Claude Code

https://claude.ai/code/session_01PUjq5rfL3s7TbKS3PeAE5K

[rustbot]

Some changes occurred in a solarish module

cc @jclulow, @pfmooney

[tgross35]

Rewrite commit messages and PR descriptions by hand, then you may unmark as a draft. See https://forge.rust-lang.org/policies/llm-usage.html#-banned.