ext2: trivial fix to comment for ext2_free_blocks

The function is ext2_free_blocks(), not ext2_free_blocks_sb().
Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

fs/ext2/balloc.c

@@ -477,7 +477,7 @@ void ext2_discard_reservation(struct inode *inode)
 }
 
 /**
- * ext2_free_blocks_sb() -- Free given blocks and update quota and i_blocks
+ * ext2_free_blocks() -- Free given blocks and update quota and i_blocks
  * @inode:		inode
  * @block:		start physcial block to free
  * @count:		number of blocks to free