Revert "drm/amdgpu: fix a potential deadlock in amdgpu_bo_create_restricted()"

This reverts commit 38fc4856ad98f230bc91da0421dec69e4aee40f8, which
introduces a use-after-free.

The underlying bug should be properly fixed with "drm/ttm: never add BO
that failed to validate to the LRU list".

Cc: zhoucm1 <david1.zhou@amd.com>
Signed-off-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
Tested-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -411,11 +411,8 @@ int amdgpu_bo_create_restricted(struct amdgpu_device *adev,
 	amdgpu_cs_report_moved_bytes(adev,
 		atomic64_read(&adev->num_bytes_moved) - initial_bytes_moved);
 
-	if (unlikely(r != 0)) {
-		if (!resv)
-			ww_mutex_unlock(&bo->tbo.resv->lock);
+	if (unlikely(r != 0))
 		return r;
-	}
 
 	bo->tbo.priority = ilog2(bo->tbo.num_pages);
 	if (kernel)