MEGA65: VIC-IV RRB transparency issue

[RetroCogs]

Describe the bug
When using RRB and setting transparency using GOTOX, once transparency is set it cannot be unset for that line.

Used version of the project
Observed on version 20240620201019 next

To Reproduce
Using RRB, set transparency using color ram byte 0-bit7 and draw a character, then clear transparency using color ram byte 0-bit7.

You will notice that the following RRB chars are still transparent.

Expected behavior
Setting / clearing color ram byte0-bit7 when GOTOX is set should correctly switch between transparent and opaque.

Screenshots
Showing the sample program on Emu showing the issue.

Showing the sample program on HW with correct behavior.

Computer/Device (please complete the following information):

• Mac
• Sonoma 14.6.1

Additional context
Add any other context about the problem here.

[lgblgblgb]

As I've written on Discord: Great, thanks! As far as I can see, this is a kind of problem we had before; only setting/resetting a thing on GOTOX token but missing the "else" branch for the opposite.

[lgblgblgb]

@RetroCogs I cannot test this patch too much right now, but judging by the diff, it's quite trivial to understand what it does and how, so I think it's safe to be merged by me right now. Thanks again.