move ip.access netowrk listen (NWL) to network_listen.c

Also, we now re-start the network listen test after it has finished,
so if you run a test from ipaccess-find, the test will get re-started
and re-started all the time.
diff --git a/openbsc/include/openbsc/gsm_data.h b/openbsc/include/openbsc/gsm_data.h
index 36591cf..5ec4441 100644
--- a/openbsc/include/openbsc/gsm_data.h
+++ b/openbsc/include/openbsc/gsm_data.h
@@ -379,6 +379,9 @@
 				struct gsm_nm_state nm_state;
 			} pa;
 		} bs11;
+		struct {
+			unsigned int test_state;
+		} ipaccess;
 	};
 	struct gsm_bts_trx_ts ts[TRX_NR_TS];
 };