Call setCameraDisabled and getCameraDisabled on the parent profile

Previously, these APIs did not support explicitly querying the parent profile.
This CL allows the WP DPC to now call these methods, which means the WP DPC
can disable the camera device-wide and not just for the WP.

Bug: 138709470
Test: manual testing using Personal and WP TestDPC and Camera
      atest com.android.cts.devicepolicy.ManagedProfileTest
      atest com.android.server.devicepolicy.DevicePolicyManagerTest

Change-Id: I7e7ce7be766850c6e2f58c72a0a44990817e9b73