It needs to be if I want to be able to have several ports controlled by
one MCU. It's set as part of the FUSB configuration, not in the INT_N
struct, since the latter isn't user-initialized and may disappear
entirely in the future.
This library implements a subset of the USB Power Delivery Specification,
Revision 2.0, Version 1.3, and Revision 3.0, Version 1.1, for microcontrollers
running ChibiOS and connected to an FUSB302B USB Power Delivery PHY.