arm64: dts: qcom: sc7280: Add SAR sensors for herobrine

Add nodes for the two SX9324 SAR proximity sensors. Not all herobrine
boards have these sensors, so leave them disabled by default.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220329105854.v3.1.Icedb2e3cd5e21f3a4ec535ddf756fa44d053b6ed@changeid