Describe the bug
System list shows Arcade even when no arcade core was built and therefore nothing can be launched.

To Reproduce
Steps to reproduce the behavior:

1. Build ares without arcade cores (for example, configure with cmake .. -DARES_CORES="n64".
2. Launch ares, click on Load
3. See Arcade option

Expected behavior
I think the option should be hidden if no arcade core is available, just like all the other systems.

Screenshots