dquot: cleanup dquot drop routine

Get rid of the drop dquot operation - it is now always called from
the filesystem and if a filesystem really needs it's own (which none
currently does) it can just call into it's own routine directly.

Rename the now static low-level dquot_drop helper to __dquot_drop
and vfs_dq_drop to dquot_drop to have a consistent namespace.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c
index 9d4dcf0..9dea84e 100644
--- a/fs/reiserfs/namei.c
+++ b/fs/reiserfs/namei.c
@@ -546,7 +546,7 @@
 */
 static int drop_new_inode(struct inode *inode)
 {
-	vfs_dq_drop(inode);
+	dquot_drop(inode);
 	make_bad_inode(inode);
 	inode->i_flags |= S_NOQUOTA;
 	iput(inode);