arm64: dts: qcom: msm8916/39: Move UART pinctrl to board files

arm64: dts: qcom: msm8916/39: Move UART pinctrl to board files

In preparation of adding a new console UART specific pinctrl template, move
the pinctrl reference to the board DT part. This forces people porting new
boards to consider what exactly they need for their board.

No functional change for the boards upstream.

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Stephan Gerhold <stephan.gerhold@linaro.org>
Link: https://lore.kernel.org/r/20250422-msm8916-console-pinctrl-v2-1-f345b7a53c91@linaro.org
Signed-off-by: Bjorn Andersson <andersson@kernel.org>