Add constants for Memory-Deny-Write-Execute prctls

[rusty-snake]

Description

This PR adds constants for Memory-Deny-Write-Execute prctls added in Linux 6.3 (PR_MDWE_NO_INHERIT Linux 6.6).

Sources

https://github.com/torvalds/linux/blob/3bde70a2c82712f05c7220b8b94fc2cbdf7fbfe0/include/uapi/linux/prctl.h#L287-L292

Checklist

• Relevant tests in libc-test/semver have been updated
• No placeholder or unstable values like *LAST or *MAX are
  included (see #3131)
• Tested locally (cd libc-test && cargo test --target mytarget);
  especially relevant for platforms that may not be checked in CI

---

@rustbot label +stable-nominated

[rustbot]

r? @tgross35

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[rusty-snake]

I'm not sure if the CI failure is because architecture or libc.

[tgross35]

It's probably just that everything in CI running musl is very outdated, I assume they should be available since they are uapi. Cc @maurer in case that is not accurate.

Assuming it's just a CI thing, you can update libc-test/build.rs to skip these on the relevant platform.

@rustbot author

[rustbot]

Reminder, once the PR becomes ready for a review, use @rustbot ready.