Core info is not detected when loading a core outside the standard cores directory

Description

If you load an emulator core that isn't in the usual cores directory, you will be able to play it just fine, but it won't match it with any core info file, which leads to you not being able to savestate due to it not knowing the core has this capability.

You can load a core outside of the usual directory either by launching content directly using the -L command line parameter, or by having the core in a subdirectory of the cores directory, and then loading it from the RetroArch UI.

Expected behavior

The core info should be matched based on the filename regardless of whether the core is in the standard location or not

Actual behavior

The core info is only matched to the core if it is in the directory defined by the libretro_directory directory (must be exactly that directory and not a subdirectory)

Start by tracing core loading through the -L command-line path and the libretro_directory lookup, then inspect where core info files are matched. Reproduce the issue with a core outside the standard directory and with a core in a subdirectory. Done means matching uses the core filename in both cases and savestate capability is recognized.