f2fs: fix typo

Fix typo and some grammatical errors.

The words "filesystem" and "readahead" are being used without the space treewide.

Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 27b0377..eb407d2 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -229,7 +229,7 @@
 	f2fs_delete_entry(de, page, inode);
 	f2fs_unlock_op(sbi);
 
-	/* In order to evict this inode,  we set it dirty */
+	/* In order to evict this inode, we set it dirty */
 	mark_inode_dirty(inode);
 fail:
 	trace_f2fs_unlink_exit(inode, err);