CFG: Implemented the GetConfigInfoBlk2 function.

Added a "config" file to the CFG process service (CFG:U), and added a few default blocks to it.

Implemented GetSystemModel and GetModelNintendo2DS
We do this in a lot of other places already, but.. what is the actual reason of having all of these in file-global scope instead of making it a member of the `Interface` class?