drm/amdgpu/gfx10: drop unused variable

Just check the return value directly.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c

@@ -7159,15 +7159,13 @@ static int gfx_v10_0_hw_init(void *handle)
 static int gfx_v10_0_hw_fini(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
-	int r;
 
 	amdgpu_irq_put(adev, &adev->gfx.priv_reg_irq, 0);
 	amdgpu_irq_put(adev, &adev->gfx.priv_inst_irq, 0);
 
 	if (!adev->no_hw_access) {
 		if (amdgpu_async_gfx_ring) {
-			r = amdgpu_gfx_disable_kgq(adev, 0);
-			if (r)
+			if (amdgpu_gfx_disable_kgq(adev, 0))
 				DRM_ERROR("KGQ disable failed\n");
 		}