Migrate split.soft_serial_pin to split.serial.pin
* initial * Update keyboards/sofle/info.json Co-authored-by: Joel Challis <git@zvecr.com> * Update keyboards/sofle/info.json Co-authored-by: Drashna Jaelre <drashna@live.com> --------- Co-authored-by: Joel Challis <git@zvecr.com> Co-authored-by: Drashna Jaelre <drashna@live.com>