update release run and variables in templates

priv/templates/otp_lib.template

@@ -1,3 +1,4 @@
+{variables, []}.
 {template, "app.erl", "src/{{appid}}_app.erl"}.
 {template, "sup.erl", "src/{{appid}}_sup.erl"}.
 {template, "otp_lib.app.src", "src/{{appid}}.app.src"}.

priv/templates/otp_rel.template

@@ -1,3 +1,4 @@
+{variables, []}.
 {template, "app.erl", "apps/{{appid}}/src/{{appid}}_app.erl"}.
 {template, "sup.erl", "apps/{{appid}}/src/{{appid}}_sup.erl"}.
 {template, "otp_app.app.src", "apps/{{appid}}/src/{{appid}}.app.src"}.

src/rebar_prv_release.erl

@@ -31,6 +31,5 @@ init(State) ->
 
 -spec do(rebar_state:t()) -> {ok, rebar_state:t()} | relx:error().
 do(Config) ->
-    RelxConfig = rebar_state:get_local(Config, relx, []),
     relx:main("release"),
     {ok, Config}.