ext4: clean up kerneldoc warnigns when building with W=1

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

fs/ext4/dir.c

@@ -33,6 +33,9 @@
 static int ext4_dx_readdir(struct file *, struct dir_context *);
 
 /**
+ * is_dx_dir() - check if a directory is using htree indexing
+ * @inode: directory inode
+ *
  * Check if the given dir-inode refers to an htree-indexed directory
  * (or a directory which could potentially get converted to use htree
  * indexing).