arm64: dts: qcom: Add pm7250b PMIC

PM7250B is a PMIC primarily used for charging and fuel gauge but also
has some of the standard functionality like temp-alarm, adc, etc.

Add the .dtsi with some of the functionality added.

Signed-off-by: Luca Weiss <luca.weiss@fairphone.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220902111055.106814-2-luca.weiss@fairphone.com