net: app: Print info if address family is not set properly

If the IP address family is not set to correct value, then print
information about it.

Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>

subsys/net/lib/app/net_app.c

@@ -115,6 +115,9 @@ char *_net_app_sprint_ipaddr(char *buf, int buflen,
 		snprintk(buf, buflen, "%s:%u", ipaddr,
 			 ntohs(net_sin(addr)->sin_port));
 #endif
+	} else {
+		snprintk(buf, buflen, "<AF_UNSPEC %d>",
+			 addr->sa_family);
 	}
 
 	return buf;