ext2: remove the redundant comment for ext2_export_ops

The comment is outdated and isn't particularly informative anyway - NULL
meaning the default behavior is very common in kernel. And we really set about
half of entries. So remove the whole comment for ext2_export_ops.
Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

fs/ext2/super.c

@@ -352,11 +352,6 @@ static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
 				    ext2_nfs_get_inode);
 }
 
-/* Yes, most of these are left as NULL!!
- * A NULL value implies the default, which works with ext2-like file
- * systems, but can be improved upon.
- * Currently only get_parent is required.
- */
 static const struct export_operations ext2_export_ops = {
 	.fh_to_dentry = ext2_fh_to_dentry,
 	.fh_to_parent = ext2_fh_to_parent,