dquot: cleanup dquot initialize routine

Get rid of the initialize 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_initialize helper to __dquot_initialize
and vfs_dq_init to dquot_initialize 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/ext4/super.c b/fs/ext4/super.c
index 035516c8..edcf3b0 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1013,7 +1013,6 @@
 				const char *data, size_t len, loff_t off);
 
 static const struct dquot_operations ext4_quota_operations = {
-	.initialize	= dquot_initialize,
 #ifdef CONFIG_QUOTA
 	.get_reserved_space = ext4_get_reserved_space,
 #endif
@@ -1931,7 +1930,7 @@
 		}
 
 		list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
-		vfs_dq_init(inode);
+		dquot_initialize(inode);
 		if (inode->i_nlink) {
 			ext4_msg(sb, KERN_DEBUG,
 				"%s: truncating inode %lu to %lld bytes",
@@ -3700,7 +3699,7 @@
  * Process 1                         Process 2
  * ext4_create()                     quota_sync()
  *   jbd2_journal_start()                  write_dquot()
- *   vfs_dq_init()                         down(dqio_mutex)
+ *   dquot_initialize()                         down(dqio_mutex)
  *     down(dqio_mutex)                    jbd2_journal_start()
  *
  */