xfs: calculate XFS_TRANS_QM_DQALLOC space log reservation at mount time

The disk quota allocation log space reservation is calcuated at runtime,
this patch does it at mount time.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
CC: Dave Chinner <david@fromorbit.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 9baa7e0..fc500c6 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -42,6 +42,7 @@
 	uint	tr_growrtfree;	/* grow realtime freeing */
 	uint	tr_qm_sbchange;	/* change quota flags */
 	uint	tr_qm_setqlim;	/* adjust quota limits */
+	uint	tr_qm_dqalloc;	/* allocate quota on disk */
 } xfs_trans_reservations_t;
 
 #ifndef __KERNEL__