wcte11xp: Fix BLUE (AIS) alarm detection

The XAIS bit to check in the FRS0 register is at 0x40, and not 0x4.

If only the original authors had the wisdom to use #defines for those
bits, and re-used those bits across the drivers (wct4xxp, wcte43x
and wcte13xp get this right!).

drivers/dahdi/wcte11xp.c

@@ -1278,7 +1278,7 @@ static void t1_check_alarms(struct t1 *wc)
 			wc->alarmcount++;
 	} else
 		wc->alarmcount = 0;
-	if (c & 0x4)
+	if (c & 0x40)
 		alarms |= DAHDI_ALARM_BLUE;
 
 	if (((!wc->span.alarms) && alarms) ||