bssgp: Return the gprs_bssgp_pcu instance from create/connect

This can be used to install handlers/testcases to register
callbacks and other data.
diff --git a/src/gprs_bssgp_pcu.h b/src/gprs_bssgp_pcu.h
index 15c8d9f..2d96032 100644
--- a/src/gprs_bssgp_pcu.h
+++ b/src/gprs_bssgp_pcu.h
@@ -41,7 +41,24 @@
 #define NS_HDR_LEN 4
 #define IE_LLC_PDU 14
 
-int gprs_bssgp_create_and_connect(struct gprs_rlcmac_bts *bts, uint16_t local_port,
+struct gprs_bssgp_pcu {
+	struct gprs_nsvc *nsvc;
+	struct bssgp_bvc_ctx *bctx;
+
+	struct gprs_rlcmac_bts *bts;
+
+	struct osmo_timer_list bvc_timer;
+
+	int nsvc_unblocked;
+
+	int bvc_sig_reset;
+	int bvc_reset;
+	int bvc_unblocked;
+	int exit_on_destroy;
+};
+
+struct gprs_bssgp_pcu *gprs_bssgp_create_and_connect(struct gprs_rlcmac_bts *bts,
+		uint16_t local_port,
 		uint32_t sgsn_ip, uint16_t sgsn_port, uint16_t nsei,
 		uint16_t nsvci, uint16_t bvci, uint16_t mcc, uint16_t mnc,
 		uint16_t lac, uint16_t rac, uint16_t cell_id);