arm64: dts: qcom: msm8996-tone: Enable LPG LEDs

Enable the notification LED(s) wired up to the PMI8994(6) LPG.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230413-tone_led-v1-1-bc3c73393bfa@linaro.org