qcacmn: fix invalid access to hif_ext_group issue

hif_ext_group is not initialized if DP interrupt is not registed
like monitor mode, invalid access will happen in function
hif_hist_record_event.

if hif_num_extgroup is 0, stop access to hif_ext_group member.

Change-Id: Id4432577446caa8887ca6d1fb8b669dda8c9fdf3
CRs-Fixed: 2475506

hif/src/hif_exec.c

@@ -53,7 +53,7 @@ void hif_hist_record_event(struct hif_opaque_softc *hif_ctx,
 	struct hif_event_record *record;
 	int record_index;
 
-	if (!event)
+	if (!hif_state->hif_num_extgroup)
 		return;
 
 	if (scn->event_disable_mask & BIT(event->type))