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/super.c b/fs/reiserfs/super.c
index 6b24e70..34f7cd0 100644
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -580,7 +580,7 @@
 
 static void reiserfs_clear_inode(struct inode *inode)
 {
-	vfs_dq_drop(inode);
+	dquot_drop(inode);
 }
 
 #ifdef CONFIG_QUOTA
@@ -623,7 +623,6 @@
 
 static const struct dquot_operations reiserfs_quota_operations = {
 	.initialize = dquot_initialize,
-	.drop = dquot_drop,
 	.write_dquot = reiserfs_write_dquot,
 	.acquire_dquot = reiserfs_acquire_dquot,
 	.release_dquot = reiserfs_release_dquot,