Whitelist android.permission.MODIFY_PHONE_STATE for AndroidAutoStub

common/proprietary/product/etc/permissions/privapp-permissions-mtg.xml

@@ -1,5 +1,9 @@
 <?xml version="1.0" encoding="utf-8"?>
 <permissions>
+    <privapp-permissions package="com.google.android.projection.gearhead">
+        <permission name="android.permission.MODIFY_PHONE_STATE"/>
+    </privapp-permissions>
+
     <privapp-permissions package="com.google.android.googlequicksearchbox">
         <permission name="android.permission.CAPTURE_MEDIA_OUTPUT"/>
         <permission name="android.permission.QUERY_USERS"/>