fanotify: create helper fanotify_mark_user_flags()

To translate from fsnotify mark flags to user visible flags.

Link: https://lore.kernel.org/r/20220422120327.3459282-13-amir73il@gmail.com


Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>