tools/intel_vbt_decode: Decode more child dev fields

Decode a bunch of newish child dev fields:
- disable_compression_for_ext_disp
- lttpr_non_transparent
- dp_port_trace_length
- tbt

Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>