drm/amd/display: Avoid HDCP initialization in devices without output

The HDCP feature requires at least one connector attached to the device;
however, some GPUs do not have a physical output, making the HDCP
initialization irrelevant. This patch disables HDCP initialization when
the graphic card does not have output.

Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

Author: Rodrigo Siqueira

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

@@ -1041,7 +1041,7 @@ static int amdgpu_dm_init(struct amdgpu_device *adev)
 	amdgpu_dm_init_color_mod();
 
 #ifdef CONFIG_DRM_AMD_DC_HDCP
-	if (adev->asic_type >= CHIP_RAVEN) {
+	if (adev->dm.dc->caps.max_links > 0 && adev->asic_type >= CHIP_RAVEN) {
 		adev->dm.hdcp_workqueue = hdcp_create_workqueue(adev, &init_params.cp_psp, adev->dm.dc);
 
 		if (!adev->dm.hdcp_workqueue)