arm64: dts: qcom: qcs6490-rb3gen2: Configure onboard LEDs

RB3 Gen2 has a trio of LEDs connected to the PM8350C's Light Pulse
Generator. Describe them.

Use the "red channel" as a panic indicator by default.

Signed-off-by: Konrad Dybcio <quic_kdybcio@quicinc.com>
[bjorn: Corrected colors]
Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20241004-rb3gen2-leds-v1-2-437cdbb4f6c0@oss.qualcomm.com


Signed-off-by: Bjorn Andersson <andersson@kernel.org>