[Feature] Turn off more peripherals while charging when off #2253
Description
The Prime Hub has to remain on while charging. We just turn off the LEDs so it appears off. There are a few more things we could turn off to save a little bit of power and other wakeup events. We already stop the UART processes since the port code overhaul.
The IMU is perhaps the only one that could make a small difference and doesn't need to be on. I was debugging this one today as part of #2251 and it occurred to me it just runs forever when it probably doesn't need to.
We've added away to gracefully request processes to end, so this is now quite easy to do.