[Auditbeat] Unsupported syscalls: umount for x86_64

[Coolgum15 (Cole Watkins)]

When adding new syscalls to auditbeat on a RHEL 9.2 VM, I found that only umount2 is supported.

Errors:

[andrewkroh]

There is no umount syscall on x86_64 so that error is expected.

Linux x86_64 has umount2.