drm/amdgpu: Add an ATPX quirk for hybrid laptop

commit 13b40935cf64f59b93cf1c716a2033488e5a228c upstream.

_PR3 doesn't seem to work properly, use ATPX instead.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=104064


Reviewed-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>