[ Suggestion ] Move Windows (and other platforms?) default 'info' location to 'cores' dir

Description

The core info files currently live in a separate directory in Windows (but not in Linux) from the cores themselves. If they lived in the same location, it would be very easy to bundle info files in the repo with the core libs themselves, which would have the advantages of giving core authors more direct control over the content of the info files, remove the need to update them in a second location (i.e., the libretro-super repo) and allow updating both the core and the info with a single download from the core downloader. This also means that new cores come with their info file without needing to download it separately (though it will still have the ugly filename until the first download).

The downside is that it's messier having them both live in the same location.

I discussed this with @m4xw and @XerTheSquirrel in discord the other day, but it is pertinent to the ongoing new automated build setup.

Expected behavior

Core and info files live in the same location

Actual behavior

they are separate

Steps to reproduce the bug

1. download a core
2. have an old (or nonexistent) info file

Bisect Results

always

Version/Commit

all

• RetroArch: all

Environment information

• OS: Windows
• Compiler: unrelated

@twinaphex

Start by tracing RetroArch's Windows core and info-file locations and the core downloader, then compare how the paths are handled on Linux and other platforms. Review the ongoing automated build setup mentioned in the issue; done means core and info files use the same location without breaking downloads or platform-specific behavior.