* Instead of gpio key behavior trigger, add new kscan driver that
decorates/wraps a given kscan driver and will invoke basic system
behavior assigned to a given row + column, without the need for keymap
mapping in the matrix transform, bypassing keymaps entirely.
* Better naming for gpio-key behavior triggers.
* Tweaks to scanned behavior trigger to avoid bad semaphore use,
and reduce chance of issues with slowly scanned matrixes.
* Various code cleanups of style issues.
* Move to explicit enable of `ZMK_PM_SOFT_OFF` to turn
on the feature and use the behaviors, which matches
how other features work, and helps with split and
testing schemes.
