frame_relay: Fix null pointer dereference in DLC/PVC delete

Change-Id: I71de58f6ca15e2057f26d9c5502c8bc3e03e714f
Closes: CID#215530
diff --git a/src/gb/frame_relay.c b/src/gb/frame_relay.c
index fba31f8..ae6bbf5 100644
--- a/src/gb/frame_relay.c
+++ b/src/gb/frame_relay.c
@@ -558,7 +558,7 @@
 		dlc = osmo_fr_dlc_by_dlci(link, dlci);
 		if (!dlc) {
 			/* don't create dlc's for the ones which are about to be deleted. */
-			if (dlc->del)
+			if (pvc->delete)
 				continue;
 
 			dlc = osmo_fr_dlc_alloc(link, dlci);