drm/amdgpu: Disable GFX PG on CZ

It's causing problems with user mode queues and the HIQ, and can
lead to hard hangs during boot after programming RLC_CP_SCHEDULERS.
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>

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

@@ -1028,8 +1028,7 @@ static int vi_common_early_init(void *handle)
 		/* rev0 hardware requires workarounds to support PG */
 		adev->pg_flags = 0;
 		if (adev->rev_id != 0x00 || CZ_REV_BRISTOL(adev->pdev->revision)) {
-			adev->pg_flags |= AMD_PG_SUPPORT_GFX_PG |
-				AMD_PG_SUPPORT_GFX_SMG |
+			adev->pg_flags |= AMD_PG_SUPPORT_GFX_SMG |
 				AMD_PG_SUPPORT_GFX_PIPELINE |
 				AMD_PG_SUPPORT_CP |
 				AMD_PG_SUPPORT_UVD |