drm/radeon/kms/vm: fix possible bug in radeon_vm_bo_rmv()

The bo is removed from the list at the top of
radeon_vm_bo_rmv(), but then the list is used
in radeon_vm_bo_update_pte() to look up the vm.
remove the bo_list entry at the end of the
function instead.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Jerome Glisse <j.glisse@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/radeon_gart.c

@@ -597,13 +597,13 @@ int radeon_vm_bo_rmv(struct radeon_device *rdev,
 	if (bo_va == NULL)
 		return 0;
 
-	list_del(&bo_va->bo_list);
 	mutex_lock(&vm->mutex);
 	radeon_mutex_lock(&rdev->cs_mutex);
 	radeon_vm_bo_update_pte(rdev, vm, bo, NULL);
 	radeon_mutex_unlock(&rdev->cs_mutex);
 	list_del(&bo_va->vm_list);
 	mutex_unlock(&vm->mutex);
+	list_del(&bo_va->bo_list);
 
 	kfree(bo_va);
 	return 0;