GLK ZCODE: iOS ScummVM crashes when launching Shogun

[dfabulich]

Shogun is a Z6 game. When you launch it, ScummVM prints a warning, "The game you are about to start is not yet fully supported by ScummVM."

One of the weird things about Z6 games is that they include graphics, but the graphics are not distributed directly inside the Z6. Instead, Frotz launches the game with two files: the Z6, and a corresponding "Blorb" file that contains the graphics.

IFWiki has documentation on how to download and run Shogun with Frotz; it works fine there. ​https://www.ifwiki.org/Shogun

To repro:

1. Create a directory containing shogun-r322-s890706.z6 and shogun-r322-s890706.blb (following the instructions from the IFWiki)
2. Plug your iOS device into your Mac, and copy the files into ScummVM, as documented here ​https://docs.scummvm.org/en/v2.8.0/other_platforms/ios.html
3. Launch ScummVM, and add that directory to ScummVM. ScummVM will recognize the game as "James Clavell's Shogun"
4. Launch the game, click "Start anyway" at the error page
5. You'll see the launch screen, "SHOGUN". Press any key.

ScummVM will then crash.