linux: add seccomp user notification ioctl constants

[fullzer4]

Description

Add missing SECCOMP_IOCTL_NOTIF_* ioctl constants for Linux and Android.

These five ioctl constants are defined in the kernel's linux/seccomp.h and are used with the seccomp user notification API. The corresponding structures (seccomp_notif, seccomp_notif_resp, seccomp_notif_addfd) and flags were already added in PR #4330, but the ioctl numbers were missing.

All Linux platforms use the same ioctl numbers as they are defined using architecture-independent _IOWR and _IOW macros with a common magic number.

Sources

• SECCOMP_IOCTL_NOTIF_* definitions: https://github.com/torvalds/linux/blob/master/include/uapi/linux/seccomp.h#L140-L155
• Related PR seccomp: Add more constants from seccomp.h #4330 (added structures and flags): seccomp: Add more constants from seccomp.h #4330

Checklist

• Relevant tests in libc-test/semver have been updated
• No placeholder or unstable values like *LAST or *MAX are included
• Constants added to both Linux and Android targets

@rustbot label +stable-nominated

[rustbot]

Some changes occurred in an Android module

cc @maurer

[rustbot]

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

[fullzer4]

@rustbot ready

[rustbot]

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.