arm64: dts: qcom: sm8250-xiaomi-pipa: Add initial device tree

Initial support for Xiaomi Pad 6 tablet, that have sm8250 soc.

Signed-off-by: Luka Panio <lukapanio@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20231125220315.118922-2-lukapanio@gmail.com


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