xfs: remove use of do_div with 32-bit dividend in quota

The kbuild test robot caught this; in debug code we have another
caller of do_div with a 32-bit dividend (j) which is caught now
that we are using the kernel-supplied do_div.

None of the values used here are 64-bit; just use simple division.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

fs/xfs/xfs_qm.c

@@ -851,8 +851,8 @@ xfs_qm_reset_dqcounts(
 	 * started afresh by xfs_qm_quotacheck.
 	 */
 #ifdef DEBUG
-	j = XFS_FSB_TO_B(mp, XFS_DQUOT_CLUSTER_SIZE_FSB);
-	do_div(j, sizeof(xfs_dqblk_t));
+	j = (int)XFS_FSB_TO_B(mp, XFS_DQUOT_CLUSTER_SIZE_FSB) /
+		sizeof(xfs_dqblk_t);
 	ASSERT(mp->m_quotainfo->qi_dqperchunk == j);
 #endif
 	dqb = bp->b_addr;