VRManager: Set initial sleep state to 'AWAKE'

Problem:
Home screen isn't allowed to enter VR mode as part of boot.

Root-cause:
VRManager is not indicating VR Mode is allowed until the system sleep
state gets synchronized.
Because the initial sleep state during boot is AWAKE and remains AWAKE if no
lock-screen is set, VrManager fails to mark VrMode as available due to a
mismatch between its initial internal sleep state and the systems sleep state.
VrManager's initial sleep state is SLEEP, where the system's initial sleep
state is AWAKE.

Solution: Set VrManager's initial sleep state to AWAKE to match the system.

Bug: 35469244
Test: - Validated VrHome comes up properly
      - Tested VrMode is not allowed when the lock-screen is shown
      - Tested VrMode is not allowed when the display is off
      - Tested VrMode is allowed when no lock-screen is set AND the display
        is on.

Change-Id: I42e9da07db21b3ed034c4173fe329cbb7796ee7e