Dummy support hal driver return hidl interface.

* Simply return empty string for now.

Test: make vts.
Change-Id: Iffd8019b956bdfdf2e3a77406ab33e4a4fc3af75
diff --git a/runners/host/tcp_client/vts_tcp_client.py b/runners/host/tcp_client/vts_tcp_client.py
index a0afc1f..0e99685 100755
--- a/runners/host/tcp_client/vts_tcp_client.py
+++ b/runners/host/tcp_client/vts_tcp_client.py
@@ -226,6 +226,9 @@
             for vector_value in var_spec_msg.vector_value:
                 result.append(self.GetPythonDataOfVariableSpecMsg(vector_value))
             return result
+        elif (var_spec_msg.type == CompSpecMsg_pb2.TYPE_HIDL_INTERFACE):
+            logging.info("Val of hidl interface is not fully supported yet.")
+            return ""
 
         raise errors.VtsUnsupportedTypeError(
             "unsupported type %s" % var_spec_msg.type)