quota: rename default quotactl methods to dquot_

Follow the dquot_* style used elsewhere in dquot.c.

[Jan Kara: Fixed up missing conversion of ext2]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index df752b7..7ff43f4 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -1068,7 +1068,7 @@
 
 #ifdef CONFIG_QUOTA
 	sb->dq_op = &dquot_operations;
-	sb->s_qcop = &vfs_quotactl_ops;
+	sb->s_qcop = &dquot_quotactl_ops;
 #endif
 
 	root = ext2_iget(sb, EXT2_ROOT_INO);