in_forward: release resource on exception (CID 508219)

Signed-off-by: Eduardo Silva <[email protected]>

plugins/in_forward/fw_conn.c

@@ -147,6 +147,7 @@ struct fw_conn *fw_conn_add(struct flb_connection *connection, struct flb_in_fw_
         helo = flb_malloc(sizeof(struct flb_in_fw_helo));
         if (!helo) {
             flb_errno();
+            flb_free(conn);
             return NULL;
         }