fix(gw): start emqx-gateway after emqx restarted

apps/emqx/src/emqx.erl

@@ -257,6 +257,7 @@ emqx_feature() ->
     [ emqx_resource
     , emqx_authn
     , emqx_authz
+    , emqx_gateway
     , emqx_data_bridge
     , emqx_rule_engine
     , emqx_bridge_mqtt

apps/emqx_gateway/src/emqx_gateway_app.erl

@@ -20,8 +20,6 @@
 
 -include_lib("emqx/include/logger.hrl").
 
--emqx_plugin(?MODULE).
-
 -logger_header("[Gateway]").
 
 -export([start/2, stop/1]).