Aligns *.h and *.c to underscore naming convention.
These were kept (with warnings) for backwards compatibility with external boards/shields:
- kscan-mock.h
- matrix-transform.h
They should be removed in the future.
PR: #523
* Refactor Kyria into separate left/right "revisions"
of the Kyria shield, and include central
kyria.dtsi file with common definition.
* Fixes for keymaps to work fully with matrix
transforms that override effective rows/columns.
* Add ability for matrix transform to do row/col
offsets, which is needed for split keyboards.