[PATCH] quota: consolidate code surrounding vfs_quota_on_mount

Move some code duplicated in both callers into vfs_quota_on_mount

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jan Kara <jack@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>