Add a stub recovery UI.

This allows recovery to work on devices without screen.
The stub recovery UI does nothing except print to stdout.

Test: write 'recovery\n--wipe_data\n--reason=wipe_data_from_ota\n'
      to misc and boot to recovery on a device without screen.
Bug: 33175036

Change-Id: Icde698aa2e2e29f4b3d0532dfd3c6a939ac2bc63