seccomp: let's update @file-system a bit

seccomp: let's update @file-system a bit

Let's add fremovexattr which was the only xattr syscall so far missing
from the group, even though lremovexattr and friends where included.

Add inotify_init, which is an older (but still supported) version of
inotify_init1.

Add oldfstat, oldlstat, oldstat which are old versions of the stat
syscalls on some archs.

Add utime, which is an older more limited version of utimes and
utimensat.

Enclose the "statx" entry in some ifdeffery to ensure libseccomp
actually knows the syscall. If libseccomp doesn't know it, then we'd get
EINVAL rather than EDOM (which is what is returned if a syscall is known
but not available on the local system) when resolving the syscall name
and we really don't want that, as we use the EDOM vs. EINVAL check for
determining whether a syscall makes sense at all.

Also, order things alphabetically.