This changes lots of files to unify `board.h` across ports. It adds
`board_deinit` when CIRCUITPY_ALARM is set. `main.c` uses it to
deinit the board before deep sleeping (even when pretending.)
Deep sleep is now a two step process for the port. First, the
port should prepare to deep sleep based on the given alarms. It
should set alarms for both deep and pretend sleep. In particular,
the pretend versions should be set immediately so that we don't
miss an alarm as we shutdown. These alarms should also wake from
`port_idle_until_interrupt` which is used when pretending to deep
sleep.
Second, when real deep sleeping, `alarm_enter_deep_sleep` is called.
The port should set any alarms it didn't during prepare based on
data it saved internally during prepare.
ESP32-S2 sleep is a bit reorganized to locate more logic with
TimeAlarm. This will help it scale to more alarm types.
Fixes#3786
Currently boots on board and can connect to REPL,
but does not appear as mountable drive in OS.
Starting REPL gives the following error message:
```
You are running in safe mode which means something unanticipated happened.
Looks like our core CircuitPython code crashed hard. Whoops!
Please file an issue at https://github.com/adafruit/circuitpython/issues
with the contents of your CIRCUITPY drive and this message:
Crash into the HardFault_Handler.
```
