Move mediaprovider_app to common code

The policy under device folder will be removed for GSI, so move the
policy to common code.

Bug: 196326750
Test: build pass
Change-Id: I9544db1771ba7b94a98913bf892386f95cf919be
diff --git a/private/mediaprovider_app.te b/private/mediaprovider_app.te
index e8a85e5..5f14ba4 100644
--- a/private/mediaprovider_app.te
+++ b/private/mediaprovider_app.te
@@ -57,3 +57,5 @@
 get_prop(mediaprovider_app, drm_service_config_prop)
 
 allow mediaprovider_app gpu_device:dir search;
+
+dontaudit mediaprovider_app sysfs_vendor_sched:dir search;