arm64: dts: qcom: msm8916-acer-a1-724: Add initial device tree

Acer Iconia Talk S A1-724 is a tablet using the MSM8916 SoC released
in 2014.

Note: The original firmware from Acer can only boot 32-bit kernels.
To boot arm64 kernels it is necessary to flash 64-bit TZ/HYP firmware
with EDL, e.g. taken from the DragonBoard 410c. This works because Acer
didn't set up (firmware) secure boot.

Add a device tree for with initial support for:

- GPIO keys
- pm8916-vibrator
- SDHCI (internal and external storage)
- USB Device Mode
- UART
- WCNSS (WiFi/BT)
- Regulators

Signed-off-by: Lin, Meng-Bo <linmengbo0689@protonmail.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20221123033817.149007-1-linmengbo0689@protonmail.com