Adding support for katana60 rev2

[swampmonster]

Description

This change adds VIA support to the katana60 rev2 board. I spoke to @rominronin to make sure that
we were not duplicating work and that was not the case. He approved of me adding this so here it is.

The defaults were chosen based on my personal board but can always be changed.

QMK Pull Request

qmk/qmk_firmware#10442

Checklist

• The QMK source code follows the guide here: https://caniusevia.com/docs/configuring_qmk
• The VIA definition follows the guide here: https://caniusevia.com/docs/layouts
• I have tested this keyboard definition using VIA's "Design" tab.
• I have tested this keyboard definition with firmware on a device.
• I have assigned alpha keys and modifier keys with the correct colors.
• The Vendor ID is not 0xFEED