Closes: #7017
* Remove the 'GP23' alias for CYW1
* Remove the 'CYW0' alias for CYW0
* Switch VBUS_SENSE to CYW2, remove 'GP24' alias
Code that wants to use SMPS_MODE, VBUS_SENSE and LED while being
portable to the W and non-W variants should use those names, not alias
names.
* Remove A3 / VOLTAGE_MONITOR
Right now this cannot be used. The ability to check the voltage monitor
should be added back in some fashion in the future.
Jeff Epler