uboot-phytec

power: add driver for K3 Adaptive Voltage Scaling Class 0

Adaptive Voltage Scaling is a technology used in TI SoCs to optimize
the operating voltage based on characterization data written to efuse
during production. Add a driver to support this feature for K3 line of
SoCs, initially for AM65x.

Signed-off-by: Tero Kristo <t-kristo@ti.com>