monitor: Fix parsing of LE Terminate BIG Complete event

LE Terminate BIG Complete event format Subevent_Code, BIG_Handle and
Reason but the last two were swapped.
diff --git a/monitor/bt.h b/monitor/bt.h
index 644c97c..7aa016a 100644
--- a/monitor/bt.h
+++ b/monitor/bt.h
@@ -3649,8 +3649,8 @@
 
 #define BT_HCI_EVT_LE_BIG_TERMINATE		0x1c
 struct bt_hci_evt_le_big_terminate {
-	uint8_t  reason;
 	uint8_t  handle;
+	uint8_t  reason;
 } __attribute__ ((packed));
 
 #define BT_HCI_EVT_LE_BIG_SYNC_ESTABILISHED	0x1d