feat: add patches dir: data/patches

add patch dir for convenient online patching.

etc/emqx_cloud/vm.args

@@ -113,3 +113,6 @@
 ## Specifies how long time (in milliseconds) to spend shutting down the system.
 ## See: http://erlang.org/doc/man/erl.html
 -shutdown_time 30000
+
+## patches dir
+-pa {{ platform_data_dir }}/patches

etc/emqx_edge/vm.args

@@ -112,3 +112,5 @@
 ## See: http://erlang.org/doc/man/erl.html
 -shutdown_time 10000
 
+## patches dir
+-pa {{ platform_data_dir }}/patches

rebar.config.erl

@@ -310,6 +310,7 @@ relx_overlay(ReleaseType) ->
     , {mkdir, "data/"}
     , {mkdir, "data/mnesia"}
     , {mkdir, "data/configs"}
+    , {mkdir, "data/patches"}
     , {mkdir, "data/scripts"}
     , {template, "data/loaded_plugins.tmpl", "data/loaded_plugins"}
     , {template, "data/loaded_modules.tmpl", "data/loaded_modules"}