drm/amd/display: add S/G support for Vangogh

[Why]
Scatter/gather feature is supported on Vangogh.

[How]
Add GTT domain support for Vangogh to enable
display buffers in system memory.
Signed-off-by: Roman Li <roman.li@amd.com>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_display.c

@@ -522,6 +522,7 @@ uint32_t amdgpu_display_supported_domains(struct amdgpu_device *adev,
 				domain |= AMDGPU_GEM_DOMAIN_GTT;
 			break;
 		case CHIP_RENOIR:
+		case CHIP_VANGOGH:
 			domain |= AMDGPU_GEM_DOMAIN_GTT;
 			break;