drm/amdgpu: add missing pci_disable_device() in amdgpu_pmops_runtime_resume()

Add missing pci_disable_device() if amdgpu_device_resume() fails.

Fixes: 8e4d5d43 ("drm/amdgpu: Handling of amdgpu_device_resume return value for graceful teardown")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>