drm/amdgpu: disable system memory page tables for now

We hit a problem with IOMMU with that. Disable until we have time to
debug further.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -847,9 +847,6 @@ static void amdgpu_vm_bo_param(struct amdgpu_device *adev, struct amdgpu_vm *vm,
 	bp->size = amdgpu_vm_bo_size(adev, level);
 	bp->byte_align = AMDGPU_GPU_PAGE_SIZE;
 	bp->domain = AMDGPU_GEM_DOMAIN_VRAM;
-	if (bp->size <= PAGE_SIZE && adev->asic_type >= CHIP_VEGA10 &&
-	    adev->flags & AMD_IS_APU)
-		bp->domain |= AMDGPU_GEM_DOMAIN_GTT;
 	bp->domain = amdgpu_bo_get_preferred_pin_domain(adev, bp->domain);
 	bp->flags = AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS |
 		AMDGPU_GEM_CREATE_CPU_GTT_USWC;