Grant MODIFY_PHONE_STATE by default for Android Auto

Fixes: https://gitlab.com/MindTheGapps/vendor_gapps/-/issues/26

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

@@ -4,6 +4,7 @@
     package="com.google.android.projection.gearhead"
     sha256-cert-digest="FD:B0:0C:43:DB:DE:8B:51:CB:31:2A:A8:1D:3B:5F:A1:77:13:AD:B9:4B:28:F5:98:D7:7F:8E:B8:9D:AC:EE:DF">
     <!-- Gearhead legacy -->
+    <permission name="android.permission.MODIFY_PHONE_STATE" fixed="false" />
     <permission name="android.permission.READ_PHONE_STATE" fixed="false" />
     <permission name="android.permission.CALL_PHONE" fixed="false" />
     <permission name="android.permission.READ_CALL_LOG" fixed="false" />