Abort running transactions when switching to refereeGrant mode.

Two reasons:
* Other nodes can abort their tx'es because of nConfigChanges changed.
We can force them not to do that by not allowing that for nodes that
not online, but that requires more accurate work
* Also we use this function to cancel transactions after hard reboot.
In that case we also better abort them, because client didn't saw
their commit.

Author: kelvich

multimaster.c

@@ -2030,7 +2030,7 @@ MtmPollStatusOfPreparedTransactions(bool majorMode)
 
 			if (majorMode)
 			{
-				MtmFinishPreparedTransaction(ts, ts->status != TRANSACTION_STATUS_IN_PROGRESS);
+				MtmFinishPreparedTransaction(ts, false);
 			}
 			else
 			{