dm log: userspace fix incorrect luid cast in userspace_ctr

mips:

drivers/md/dm-log-userspace-base.c: In function `userspace_ctr':
drivers/md/dm-log-userspace-base.c:159: warning: cast from pointer to integer of different size

Cc: stable@kernel.org
Cc: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

drivers/md/dm-log-userspace-base.c

@@ -156,7 +156,7 @@ static int userspace_ctr(struct dm_dirty_log *log, struct dm_target *ti,
 	}
 
 	/* The ptr value is sufficient for local unique id */
-	lc->luid = (uint64_t)lc;
+	lc->luid = (unsigned long)lc;
 
 	lc->ti = ti;