GPRS GMM: When we receive a RA UPD REQ, we are NORMAL even after SUSPEND

There is no explicit BSSGP RESUME in case the MS sends a RA UPD REQ
after being in SUSPEND previously.
diff --git a/openbsc/src/gprs/gprs_gmm.c b/openbsc/src/gprs/gprs_gmm.c
index 73f62d3..cc9d297 100644
--- a/openbsc/src/gprs/gprs_gmm.c
+++ b/openbsc/src/gprs/gprs_gmm.c
@@ -992,6 +992,9 @@
 		process_ms_ctx_status(mmctx, pdp_status);
 	}
 
+	/* Make sure we are NORMAL (i.e. not SUSPENDED anymore) */
+	mmctx->mm_state = GMM_REGISTERED_NORMAL;
+
 	/* Send RA UPDATE ACCEPT */
 	return gsm48_tx_gmm_ra_upd_ack(mmctx);
 }