Add MS_NOSYMFOLLOW flag

[tedbrandston]

Description

Adds the MS_NOSYMFOLLOW flag from linux/mount.h

MS_NOSYMFOLLOW (since Linux 5.10) disallows automatic following of symlinks.

Sources

https://github.com/torvalds/linux/blob/ab59a8605604f71bbbc16077270dc3f39648b7fc/include/uapi/linux/mount.h

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]

r? @tgross35

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[tgross35]

The change looks fine but semver/linux.txt needs to be updated. Any reason this is marked as a draft?

[tedbrandston]

The template said to mark it as a draft if you weren't sure about the checklist items.

I'll take a look at updating the semver, but won't have a chance to test locally for a while. Is local testing necessary for a change like this?

[tgross35]

It's usually good to run locally if possible but don't worry about it here, CI covers testing for this platform. Just update the semver file and squash and this should be good to go.

[tedbrandston]

Looks like the freebsd failures are present on other recent PRs. I've updated linux.txt and run the tests locally (they pass).

[tgross35]

Thank you!