The SC8280XP contains two additional tsens instances, providing among
other things thermal measurements for the GPU.

Add these and a GPU thermal-zone.
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Link: https://lore.kernel.org/r/20240206-sc8280xp-tsens2_3-v3-1-4577b3b38ea8@quicinc.com
[bjorn: s/cpu-crit/gpu-crit/]
Signed-off-by: Bjorn Andersson <andersson@kernel.org>