inotify: report both events on parent and child with single callback

inotify: report both events on parent and child with single callback

fsnotify usually calls inotify_handle_event() once for watching parent
to report event with child's name and once for watching child to report
event without child's name.

Do the same thing with a single callback instead of two callbacks when
marks iterator contains both inode and child entries.

Link: https://lore.kernel.org/r/20200716084230.30611-13-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>