drm/amd/display: Don't repeat DAC load detection

drm/amd/display: Don't repeat DAC load detection

The analog link detection code path had already performed the
DAC load detection by the time the EDID read is attempted.
So there is no need to repeat the DAC load detection,
we can know that no display is connected if no EDID is read.

Fixes: ac1bb4952267 ("drm/amd/display: Use DAC load detection on analog connectors (v2)")
Suggested-by: Alex Hung <alex.hung@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>