tools headers UAPI: sync linux/fs.h with the kernel sources

Required for a new PAGEMAP_SCAN test to verify guard region reporting.

Link: https://lkml.kernel.org/r/20250324065328.107678-3-avagin@google.com


Signed-off-by: Andrei Vagin <avagin@gmail.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>