Exporting and Importing Icons breaks BPR

[derneuere]

This is a bug when exporting and importing icons from a bundle.
The import states "Exporting (Legacy PC)", but it's not that clear, that this will break BPR.

Steps to reproduce:

• Export a .tga from an icon file and import them again.
• Start the game
• Game will crash, when viewing icon

[JeBobs]

I will have to review this functionality again, I recently made a lot of changes that should fix support for exporting and importing both legacy PC and Remastered.