xfs: stop using q_core timers in the quota code

Add timers fields to the incore dquot, and use that instead of the ones
in qcore.  This eliminates a bunch of endian conversions and will
eventually allow us to remove qcore entirely.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>

fs/xfs/xfs_dquot.h

@@ -38,6 +38,13 @@ struct xfs_dquot_res {
 	xfs_qcnt_t		hardlimit;
 	xfs_qcnt_t		softlimit;
 
+	/*
+	 * For root dquots, this is the default grace period, in seconds.
+	 * Otherwise, this is when the quota grace period expires,
+	 * in seconds since the Unix epoch.
+	 */
+	time64_t		timer;
+
 	/*
 	 * For root dquots, this is the maximum number of warnings that will
 	 * be issued for this quota type.  Otherwise, this is the number of