drm/amd/display: Adding dm controlled signal type in dc_stream

- Adding dm controlled signal type in dc_stream
- Adding fallback to dvi signal when output signal is hdmi and the connector
  type is not

Signed-off-by: Sylvia Tsai <sylvia.tsai@amd.com>
Acked-by: Harry Wentland <Harry.Wentland@amd.com>
Reviewed-by: Sylvia Tsai <Sylvia.Tsai@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>