arm64: dts: qcom: Add the Nothing Phone (3a)

arm64: dts: qcom: Add the Nothing Phone (3a)

Add a devicetree for the Nothing Phone (3a) smartphone, which is based
on the Milos/SM7635 SoC.

Supported functionality as of this initial submission:
* Camera flash/torch LED
* Debug UART
* Glyph LEDs (AW20036)
* PMIC-GLINK (Charger, Fuel gauge, USB-C mode switching)
* Assistant Key, Power Button, Volume Keys
* Regulators (PM7550, PM8550VS, PMR735B)
* Remoteprocs (ADSP, CDSP, MPSS, WPSS)
* USB (USB2 + FSA4480)

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Alexander Koskovich <akoskovich@pm.me>
Link: https://lore.kernel.org/r/20260323-asteroids-v2-3-1a35fa9e178a@pm.me
Signed-off-by: Bjorn Andersson <andersson@kernel.org>