drm/amd/display: Fix Synaptics Cascaded Panamera DSC Determination

Synaptics Cascaded Panamera topology needs to unconditionally
acquire root aux for dsc decoding.
Reviewed-by: Roman Li <roman.li@amd.com>
Signed-off-by: Fangzhi Zuo <Jerry.Zuo@amd.com>
Signed-off-by: Zaeem Mohamed <zaeem.mohamed@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c

@@ -253,7 +253,7 @@ static bool validate_dsc_caps_on_connector(struct amdgpu_dm_connector *aconnecto
 		aconnector->dsc_aux = &aconnector->mst_root->dm_dp_aux.aux;
 
 	/* synaptics cascaded MST hub case */
-	if (!aconnector->dsc_aux && is_synaptics_cascaded_panamera(aconnector->dc_link, port))
+	if (is_synaptics_cascaded_panamera(aconnector->dc_link, port))
 		aconnector->dsc_aux = port->mgr->aux;
 
 	if (!aconnector->dsc_aux)