* To avoid spurious CDC ACM instances when usint CDC ACM for something
other than logging, move to the approach used by Zephyr of using a
snippet to redirect console output to a CDC ACM node added by the
snippet. Remove all the existing static CDC ACM nodes.
* Add new `zmk-usb-logging` snippet that mirrors the upstream
`cdc-acm-logging` snippet, but still does our extra USB logging
configuration.
* Updated logging docs accordingly.
Co-authored-by: Cem Aksoylar <caksoylar@users.noreply.github.com>