Add drmserver permission for ephemeral apps

so they can use MediaExtractor too.

Bug: 67406992
Test: yes
Change-Id: Iaacadc13b1fc032fe31eea1f3ecbbbabb741470a
(cherry picked from commit 3235963830dd41b82b89c375d0147534f8c0ee12)
diff --git a/private/ephemeral_app.te b/private/ephemeral_app.te
index 872892b..d5d88ef 100644
--- a/private/ephemeral_app.te
+++ b/private/ephemeral_app.te
@@ -31,6 +31,7 @@
 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 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;