arm64: dts: qcom: sdm630: add UART pin functions

Configure UART1 and UART2 pins to respective functions in default state,
otherwise the pins might stay as GPIOs.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20221011190231.76784-1-krzysztof.kozlowski@linaro.org