xfs: fix the warning message in xfs_validate_sb_common()

Fix this error message to complain about project and group quota flag
bits instead of "PUOTA" and "QUOTA".

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>