Add drmserver permission for ephemeral apps

so they can use MediaExtractor too.

Bug: 67406992
Bug: 80483645
Test: yes
Change-Id: Iaacadc13b1fc032fe31eea1f3ecbbbabb741470a
Merged-In: Iaacadc13b1fc032fe31eea1f3ecbbbabb741470a

private/ephemeral_app.te

@@ -28,6 +28,7 @@ allow ephemeral_app mediacodec_service:service_manager find;
 allow ephemeral_app mediametrics_service:service_manager find;
 allow ephemeral_app mediadrmserver_service:service_manager find;
 allow ephemeral_app mediacasserver_service:service_manager find;
+allow ephemeral_app drmserver_service:service_manager find;
 allow ephemeral_app surfaceflinger_service:service_manager find;
 allow ephemeral_app radio_service:service_manager find;
 allow ephemeral_app ephemeral_app_api_service:service_manager find;