fusb302:
- Find a better logging scheme, at least not having the same debugging/logging
  code replicated here and in tcpm
- Find a non-hacky way to coordinate between PM and I2C access
- Documentation? The FUSB302 datasheet provides information on the chip to help
  understand the code. But it may still be helpful to have a documentation.
- We may want to replace the  "fcs,max-snk-microvolt", "fcs,max-snk-microamp",
  "fcs,max-snk-microwatt" and "fcs,operating-snk-microwatt" device(tree)
  properties with properties which are part of a generic type-c controller
  devicetree binding.