sepolicy: Give access to ahal to flinger standby prop

Allow Vendor Audio HAL to update Audio Flinger standby
idle timeout.

Bug: 181967247
Change-Id: I7ae992bde5fdcf81ce2ca7a5a93e5e70aab1b56c
diff --git a/private/compat/30.0/30.0.cil b/private/compat/30.0/30.0.cil
index 2b2b04a..c158a30 100644
--- a/private/compat/30.0/30.0.cil
+++ b/private/compat/30.0/30.0.cil
@@ -1299,6 +1299,7 @@
 (typeattributeset default_android_vndservice_30_0 (default_android_vndservice))
 (typeattributeset default_prop_30_0 (
     default_prop
+    audio_config_prop
     build_config_prop
     suspend_prop
     init_service_status_private_prop