Log Message:
PC6001VX: update to 4.1.2.

Upstream changes:

4.1.2 2023/01/09
* Updated PC-6001mk2/6601 compatible basic ROMs to 0.4.2.
* Fixed: Could not cancel quiting if "Confirm at exit" is checked.
* (Windows)Fixed: Katakana/Hiragana key (kana switching) not working.