fix onStop

Author: stonebuzz

app/src/main/java/org/glpi/inventory/agent/ui/ActivityMain.java

@@ -149,9 +149,9 @@ protected void onStart() {
     @Override
     protected void onStop() {
         super.onStop();
-        if (broadcastReceiver != null) {
+        if (appRestrictionChange != null) {
             unregisterReceiver(appRestrictionChange);
-            broadcastReceiver = null;
+            appRestrictionChange = null;
         }
     }