Autogenerate data in C sources when creating slices

[em-eight]

Saves us time from modifying the slices and regenerating assembly every time new data is referenced in C code. Will also probably make matching data quick, easier and more beginner friendly.

Doing that requires:

• Adding data definitions in CAsmGenerator corresponding to the data slices
• Referring to those definitions in inline assembly

Project that supports this: https://github.com/SeekyCt/spm-decomp/blob/9a91c42d748a4c9a8a1e8199e5a4d8f36792679b/src/windowdrv.c#L25

[SeekyCt]

Just to clarify, that actual c's not auto-generated yet, only the includes it uses