In #4683, tannewt noticed that uncrustify was not running on some
file in common-hal.
I investigated and found that it was not being run on a bunch of paths.
Rather than make incremental changes, I rewrote list_files to work
bsaed on regular expressions; these regular expressions are created from
the same git-style glob patterns.
I spot-checked some specific filenames after this change, and all looks good:
```
$ python3 tools/codeformat.py -v --dry-run tests/basics/int_small.py ports/raspberrypi/common-hal/pulseio/PulseIn.c extmod/virtpin.c tests/thread/thread_exit1.py ports/raspberrypi/background.h extmod/re1.5/recursiveloop.c
tools/codeformat.py -v --dry-run tests/basics/int_small.py ports/raspberrypi/common-hal/pulseio/PulseIn.c extmod/virtpin.c tests/thread/thread_exit1.py ports/raspberrypi/background.h extmod/re1.5/recursiveloop.c
uncrustify -c /home/jepler/src/circuitpython/tools/uncrustify.cfg -lC --no-backup extmod/virtpin.c ports/raspberrypi/background.h ports/raspberrypi/common-hal/pulseio/PulseIn.c
black --fast --line-length=99 -v tests/thread/thread_exit1.py
```
recursiveloop and int_small are excluded, while PulseIn, virtpin,
and background are included.
Testing running from a subdirectory (not _specifically_ supported though):
```
(cd ports && python3 ../tools/codeformat.py -v --dry-run raspberrypi/common-hal/pulseio/PulseIn.c ../extmod/virtpin.c)
../tools/codeformat.py -v --dry-run raspberrypi/common-hal/pulseio/PulseIn.c ../extmod/virtpin.c
uncrustify -c /home/jepler/src/circuitpython/tools/uncrustify.cfg -lC --no-backup ../extmod/virtpin.c raspberrypi/common-hal/pulseio/PulseIn.
```
As a side-effect, a bunch more files are re-formatted now. :-P
If one of the default pins was already in use it would crash.
The internal API has been refined to allow us to get the value
without causing an init of the singleton.
Fixes#1753
This started while adding USB MIDI support (and descriptor support is
in this change.) When seeing that I'd have to implement the MIDI class
logic twice, once for atmel-samd and once for nrf, I decided to refactor
the USB stack so its shared across ports. This has led to a number of
changes that remove items from the ports folder and move them into
supervisor.
Furthermore, we had external SPI flash support for nrf pending so I
factored out the connection between the usb stack and the flash API as
well. This PR also includes the QSPI support for nRF.
