drm/amd/display: set active bit for desktop with VSDBv3

When using freesync on desktop, need to set freesync active bit for AMD
VSDBv3 infopacket.

Tested-by: Daniel Wheeler <Daniel.Wheeler@amd.com>
Reviewed-by: Martin Leung <Martin.Leung@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Dillon Varone <Dillon.Varone@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>