xfs: Convert to using ->get_state callback

Convert xfs to use ->get_state callback instead of ->get_xstate and
->get_xstatev.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>

diff --cc fs/xfs/xfs_qm.h
Simple merge

diff --cc fs/xfs/xfs_qm_syscalls.c
Simple merge

diff --cc fs/xfs/xfs_quotaops.c
Simple merge