tools: gtp-tunnel: fix accidentally swapped ms_addr and sgsn_addr

The output was swapping the ms and the sgsn addresses.
diff --git a/tools/gtp-tunnel.c b/tools/gtp-tunnel.c
index ec091db..4980825 100644
--- a/tools/gtp-tunnel.c
+++ b/tools/gtp-tunnel.c
@@ -148,8 +148,8 @@
 	}
 
 	printf("version %u ", pdp.version);
-	printf("tid %llu ms_addr %s ", pdp.tid, inet_ntoa(pdp.sgsn_addr));
-	printf("sgsn_addr %s\n", inet_ntoa(pdp.ms_addr));
+	printf("tid %llu ms_addr %s ", pdp.tid, inet_ntoa(pdp.ms_addr));
+	printf("sgsn_addr %s\n", inet_ntoa(pdp.sgsn_addr));
 
 	return MNL_CB_OK;
 }