SMS Vscroll lock is locking 9 instead of 8 right-most columns

[helpcomputer]

If you scroll vertically on a game which uses the vscroll lock for a right-hand side HUD (e.g. Gauntlet on SMS) you will see an extra column is being locked incorrectly. You can tell it quite easily as the right-most column of the play field is not scrolling.

[irixxxx]

Acknowledged, e.g. in Line of Fire.

[irixxxx]

fixed with 7f6f684 in my repo. In with the next merge.