enum: print out malformed uri in enum_query()

- previous error message did not show up the username part of r-uri.
  therefor debugging was difficult.

(cherry picked from commit fd3c30f)

modules/enum/enum.c

@@ -762,14 +762,15 @@ int enum_query(struct sip_msg* _msg, str* suffix, str* service)
 		return -1;
 	}
 
+	user_s = _msg->parsed_uri.user.s;
+	user_len = _msg->parsed_uri.user.len;
+
 	if (is_e164(&(_msg->parsed_uri.user)) == -1) {
-		LM_ERR("R-URI user is not an E164 number\n");
+		LM_ERR("R-URI user '<%.*s>' is not an E164 number\n",
+		user_len, user_s);
 		return -1;
 	}
 
-	user_s = _msg->parsed_uri.user.s;
-	user_len = _msg->parsed_uri.user.len;
-
 	memcpy(&(string[0]), user_s, user_len);
 	string[user_len] = (char)0;