Add missing Fanotify APIs from the libc crate into Nix.

[carlvoller]

What does this PR do

Adds support for nix to receive additional Fanotify information records (such as libc::fanotify_event_info_fid, libc::fanotify_event_info_error and libc::fanotify_event_info_pidfd)
Adds abstractions over the new fanotify structs.
Adds new InitFlags to allow receiving these new information records.

This closes #2551

Checklist:

• I have read CONTRIBUTING.md
• I have written necessary tests and rustdoc comments
• A change log has been added if this PR modifies nix's API

[carlvoller]

I'm not very sure whats going on with the solaris CI failure, but the test that is failing sys::test_uio::test_writev doesn't look related to the changes I've made.

Some guidance would be really appreciated 👍

[SteveLauC]

Hi @psumbera, could you please take a look at the Solaris CI failure? It failed in this line

nix/test/sys/test_uio.rs

Line 48 in 0f45593

let written = write_res.expect("couldn't write");

  ---- sys::test_uio::test_writev stdout ----
  thread 'sys::test_uio::test_writev' panicked at test/sys/test_uio.rs:48:29:
  couldn't write: EINVAL

[psumbera]

Hi @psumbera, could you please take a look at the Solaris CI failure? It failed in this line

nix/test/sys/test_uio.rs

Line 48 in 0f45593

let written = write_res.expect("couldn't write");

  ---- sys::test_uio::test_writev stdout ----
  thread 'sys::test_uio::test_writev' panicked at test/sys/test_uio.rs:48:29:
  couldn't write: EINVAL

I have seen this one. Seems that this one can fail randomly.

I will create PR to disable this test for Solaris. Sorry about that!

[SteveLauC]

Sorry about that!

No need to be sorry:)

I will create PR to disable this test for Solaris

Thanks, I will create an issue for this.

[SteveLauC]

I'm not very sure whats going on with the solaris CI failure, but the test that is failing sys::test_uio::test_writev doesn't look related to the changes I've made.

This test has been disabled, you can rebase your branch to fix the CI:)

[carlvoller]

Alright, just rebased 👍