fs: s/__u32/u32/ for s_fsnotify_mask

The underscore variants are for uapi whereas the non-underscore variants
are for in-kernel consumers.

Link: https://lore.kernel.org/r/20240822-anwerben-nutzung-1cd6c82a565f@braunerReviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>

include/linux/fs.h

@@ -1266,7 +1266,7 @@ struct super_block {
 	time64_t		   s_time_min;
 	time64_t		   s_time_max;
 #ifdef CONFIG_FSNOTIFY
-	__u32			s_fsnotify_mask;
+	u32			s_fsnotify_mask;
 	struct fsnotify_sb_info	*s_fsnotify_info;
 #endif