message: fix mysql->prepare no response with 0 params.
diff: @@ -1093,7 +1093,7 @@ static sw_inline int mysql_read_params(mysql_client *client)
  if (n_buf < 4)
  {
  - swTraceLog(SW_TRACE_MYSQL_CLIENT, "read eof 23.");
  + swTraceLog(SW_TRACE_MYSQL_CLIENT, "read eof [1]");
  return SW_ERR;
  }
  @@ -1118,7 +1118,7 @@ static sw_inline int mysql_read_params(mysql_client *client)
  }
  else
  {
  - swTraceLog(SW_TRACE_MYSQL_CLIENT, "read eof.");
  + swTraceLog(SW_TRACE_MYSQL_CLIENT, "read eof [2]");
  if (mysql_read_eof(client, buffer, n_buf) == 0)
  {
  @@ -1542,7 +1542,14 @@ int mysql_response(mysql_client *client)
  buffer->offset += (5 + ret);
  client->response.num_column = client->statement->field_count;
  client->response.columns = ecalloc(client->response.num_column, sizeof(mysql_field));
  + if (client->statement->param_count > 0)
  + {
  client->state = SW_MYSQL_STATE_READ_PARAM;
  + }
  + else
  + {
  + client->state = SW_MYSQL_STATE_READ_FIELD;
  + }
  break;
  }
  }
  @@ -1850,10 +1857,14 @@ static PHP_METHOD(swoole_mysql, connect)
  #endif
  {
  connector->strict_type = 1;
  - }else{
  + }
  + else
  + {
  connector->strict_type = 0;
  }
  - } else{
  + }
  + else
  + {
  connector->strict_type = 0;
  }
  