drm/amdgpu:bo_free_kernel will set ptr to NULL if freed

Signed-off-by: Monk Liu <Monk.Liu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/gfx_v8_0.c

@@ -1477,7 +1477,6 @@ static void gfx_v8_0_kiq_fini(struct amdgpu_device *adev)
 	struct amdgpu_kiq *kiq = &adev->gfx.kiq;
 
 	amdgpu_bo_free_kernel(&kiq->eop_obj, &kiq->eop_gpu_addr, NULL);
-	kiq->eop_obj = NULL;
 }
 
 static int gfx_v8_0_kiq_init(struct amdgpu_device *adev)