drm/amdgpu/display: handle aux backlight in backlight_get_brightness

commit 0ad3e64eb46d8c47de3af552e282894e3893e973 upstream.

Need to fetch it via aux.

Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@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>
1 file changed