arm64: dts: qcom: move pon reboot-modes from pm8150.dtsi to board files

Reboot modes were originally managed by PMIC pon driver on mobile/IoT
platforms, such as sm8150,sm8250,qdu1000... But recently, QCS615 is
going to adopt PSCI to manage linux reboot modes, which involves firm
wares to co-work with. In this case, reboot-modes should be removed
from pon dts node to avoid conflicting. This implies that reboot modes
go with devices rather than PMICs as well.

Signed-off-by: Tingguo Cheng <quic_tingguoc@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20241202-adds-spmi-pmic-peripherals-for-qcs615-v6-2-bdd306b4940d@quicinc.com


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