Add SECURE_* and SECBIT_* macros added in Linux 6.14.

[collinfunk]

The following macros were added in Linux 6.14 [1].

[1] torvalds/linux@a0623b2

• 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

[collinfunk]

I assume the CI failures are because they are run on older kernels?

The correct thing to do is modify libc-test/build.rs, do I understand correctly?