Revert "nat: Remember where the BTS is listening for things."

Remove the code to parse port as we need to discover the
BTS behind the nat and most likely it will have a different
port than the one advertised by the BTS.

This reverts commit c6a1fe773d16eb20d4cb1d3097761419436f4537.
diff --git a/openbsc/include/openbsc/bsc_nat.h b/openbsc/include/openbsc/bsc_nat.h
index 6de32eb..6cf20f2 100644
--- a/openbsc/include/openbsc/bsc_nat.h
+++ b/openbsc/include/openbsc/bsc_nat.h
@@ -208,6 +208,5 @@
 void bsc_mgcp_clear_endpoints_for(struct bsc_connection *bsc);
 int bsc_mgcp_parse_response(const char *str, int *code, char transaction[60]);
 int bsc_mgcp_extract_ci(const char *resp);
-int bsc_mgcp_extract_port(const char *resp);
 
 #endif
diff --git a/openbsc/src/nat/bsc_mgcp_utils.c b/openbsc/src/nat/bsc_mgcp_utils.c
index 6fc5eac..ffdc3ed 100644
--- a/openbsc/src/nat/bsc_mgcp_utils.c
+++ b/openbsc/src/nat/bsc_mgcp_utils.c
@@ -186,7 +186,7 @@
 	struct msgb *output;
 	struct bsc_endpoint *bsc_endp = NULL;
 	struct mgcp_endpoint *endp = NULL;
-	int i, code, port;
+	int i, code;
 	char transaction_id[60];
 
 	/* Some assumption that our buffer is big enough.. and null terminate */
@@ -228,9 +228,6 @@
 
 	/* make it point to our endpoint */
 	endp->ci = bsc_mgcp_extract_ci((const char *) msg->l2h);
-	port = bsc_mgcp_extract_port((const char *) msg->l2h);
-	endp->bts_rtp = htons(port);
-	endp->bts_rtcp = htons(port + 1);
 	output = bsc_mgcp_rewrite((char * ) msg->l2h, msgb_l2len(msg),
 				  bsc->nat->mgcp_cfg->source_addr, endp->rtp_port);
 
@@ -269,18 +266,6 @@
 	return ci;
 }
 
-int bsc_mgcp_extract_port(const char *str)
-{
-	int port;
-	char *res = strstr(str, "m=audio ");
-	if (!res)
-		return 0;
-
-	if (sscanf(res, "m=audio %d RTP/AVP %*d", &port) != 1)
-		return 0;
-	return port;
-}
-
 /* we need to replace some strings... */
 struct msgb *bsc_mgcp_rewrite(char *input, int length, const char *ip, int port)
 {
diff --git a/openbsc/tests/bsc-nat/bsc_nat_test.c b/openbsc/tests/bsc-nat/bsc_nat_test.c
index a859d07..5939632 100644
--- a/openbsc/tests/bsc-nat/bsc_nat_test.c
+++ b/openbsc/tests/bsc-nat/bsc_nat_test.c
@@ -505,19 +505,6 @@
 	}
 }
 
-static void test_mgcp_parse_port(void)
-{
-	int port;
-
-	fprintf(stderr, "Test MGCP port parsing.\n");
-
-	port = bsc_mgcp_extract_port(mdcx_resp);
-	if (port != 4002) {
-		fprintf(stderr, "Could not parse port. Got: %d\n", port);
-		abort();
-	}
-}
-
 int main(int argc, char **argv)
 {
 	struct debug_target *stderr_target;
@@ -533,7 +520,6 @@
 	test_mgcp_find();
 	test_mgcp_rewrite();
 	test_mgcp_parse();
-	test_mgcp_parse_port();
 	return 0;
 }