drm/amd/display: Disable freesync borderless on Renoir

[WHY]
Freesync borderless is not meant to be enabled on any APUs

[HOW]
Add is_apu cap to dcn21_resource_construct for correct recognition
Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Reviewed-by: Yongqiang Sun <yongqiang.sun@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c

@@ -1799,6 +1799,7 @@ static bool dcn21_resource_construct(
 	dc->caps.force_dp_tps4_for_cp2520 = true;
 	dc->caps.extended_aux_timeout_support = true;
 	dc->caps.dmcub_support = true;
+	dc->caps.is_apu = true;
 
 	if (dc->ctx->dce_environment == DCE_ENV_PRODUCTION_DRV)
 		dc->debug = debug_defaults_drv;