CameraService: Check if the camera is disabled via device policy by user.

The current approach to checking the camera device policy is multi-user
agnostic. This patch takes the user into account.

Test: Tested GCA with device policy set via TestDPC
Bug: 230026863
Change-Id: I3937f75ebfc219906a3c379b6b4cfacd801a40bf
Merged-In: I3937f75ebfc219906a3c379b6b4cfacd801a40bf