[WiiU] [REQ] Upgrade the WiiU Exception Handler.

This is a request to upgrade Exception Handler on WiiU.
If you've used the WiiU version of Retroarch long enough eventually you'll get an DSI Error and when you do you have to pull the plug on the WiiU to restart the Console. This obviously isn't good for the Console long term :P The amount of times I've had to pull the plug on the WiiU while testing Retroarch lol

There's an updated WiiU Exception Handler already made and used on the WiiU PPSSPP Emulator :)
When that Emulator crashes we get the similar DSI Error screen but has an added "Press Any Button to Exit" so we can exit properly without having to hard reset the Console :)

Would it be possible to use that Exception handler or even add the ability to exit a Retroarch DSI Error screen with a button press.
Here's the link to the PPSSPP Exception Handler commit...
https://github.com/aliaspider/ppsspp/commit/f3fc3d77ad7c5afb2b9cbd00860cd128eb69284e

Thank you :)

Start by reviewing the linked PPSSPP exception-handler commit and locating the WiiU exception-handler entry point in RetroArch. Done means a WiiU DSI error can be dismissed with a button press instead of requiring a hard reset.