arm64: dts: qcom: sc7180: Add prox sensor to LTE sku Lazor boards

arm64: dts: qcom: sc7180: Add prox sensor to LTE sku Lazor boards

There's a proximity sensor on Lazor devices, but only for LTE SKUs.
Enable it only on the Lazor LTE SKUs and also configure it properly so
it works.

Cc: Douglas Anderson <dianders@chromium.org>
Cc: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20201120183825.547310-1-swboyd@chromium.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>