chore: emacs mode entry comment for non-erl files

apps/emqx_gateway_coap/rebar.config

@@ -1,3 +1,4 @@
+%% -*- mode: erlang -*-
 {erl_opts, [debug_info]}.
 {deps, [
     {emqx, {path, "../emqx"}},

apps/emqx_gateway_coap/src/emqx_gateway_coap.app.src

@@ -1,3 +1,4 @@
+%% -*- mode: erlang -*-
 {application, emqx_gateway_coap, [
     {description, "CoAP Gateway"},
     {vsn, "0.1.4"},

apps/emqx_gateway_exproto/rebar.config

@@ -1,3 +1,4 @@
+%% -*- mode: erlang -*-
 {erl_opts, [debug_info]}.
 {deps, [
     {emqx, {path, "../emqx"}},

apps/emqx_gateway_exproto/src/emqx_gateway_exproto.app.src

@@ -1,3 +1,4 @@
+%% -*- mode: erlang -*-
 {application, emqx_gateway_exproto, [
     {description, "ExProto Gateway"},
     {vsn, "0.1.4"},

apps/emqx_gateway_gbt32960/rebar.config

@@ -1,6 +1,7 @@
+%% -*- mode: erlang -*-
 {erl_opts, [debug_info]}.
 {deps, [
-  {emqx, {path, "../../apps/emqx"}},
-  {emqx_utils, {path, "../emqx_utils"}},
-  {emqx_gateway, {path, "../../apps/emqx_gateway"}}
+    {emqx, {path, "../../apps/emqx"}},
+    {emqx_utils, {path, "../emqx_utils"}},
+    {emqx_gateway, {path, "../../apps/emqx_gateway"}}
 ]}.

apps/emqx_gateway_gbt32960/src/emqx_gateway_gbt32960.app.src

@@ -1,3 +1,4 @@
+%% -*- mode: erlang -*-
 {application, emqx_gateway_gbt32960, [
     {description, "GBT32960 Gateway"},
     {vsn, "0.1.0"},

apps/emqx_gateway_lwm2m/rebar.config

@@ -1,3 +1,4 @@
+%% -*- mode: erlang -*-
 {erl_opts, [debug_info]}.
 {deps, [ {emqx, {path, "../../apps/emqx"}},
          {emqx_gateway, {path, "../../apps/emqx_gateway"}}

apps/emqx_gateway_lwm2m/src/emqx_gateway_lwm2m.app.src

@@ -1,3 +1,4 @@
+%% -*- mode: erlang -*-
 {application, emqx_gateway_lwm2m, [
     {description, "LwM2M Gateway"},
     {vsn, "0.1.3"},

apps/emqx_gateway_mqttsn/src/emqx_gateway_mqttsn.app.src

@@ -1,3 +1,4 @@
+%% -*- mode: erlang -*-
 {application, emqx_gateway_mqttsn, [
     {description, "MQTT-SN Gateway"},
     {vsn, "0.1.5"},

apps/emqx_gateway_stomp/rebar.config

@@ -1,3 +1,4 @@
+%% -*- mode: erlang -*-
 {erl_opts, [debug_info]}.
 {deps, [
   {emqx, {path, "../../apps/emqx"}},

apps/emqx_gateway_stomp/src/emqx_gateway_stomp.app.src

@@ -1,3 +1,4 @@
+%% -*- mode: erlang -*-
 {application, emqx_gateway_stomp, [
     {description, "Stomp Gateway"},
     {vsn, "0.1.3"},