Fixed Transparent Character Prefcolor/Sprite reversion

Only noticeable on certain character WADs, but if a character sprite has a base color other than green, and its prefcolor is different than that color (example, Espio uses blue for his color-changing areas, and his prefcolor is purple), they will revert to the sprite's base color when the sprite turns transparent from zooming in the camera. (example, Espio turns blue while transparent)

The best place to see this effect is against a predominantly white area, such as snow, or RedXVI's roof.