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
Key release events released keys on the wrong layer if the 'top layer'
was not &trans above the &mo key.
base <&mo 1>
layer 1 <&kp B>
This was caused by overwriting
`zmk_keymap_active_behavior_layer[position]` after the &mo key was
handled.
