With my previous changes Dolphin would fail to create the user directory if it didn't exist, and would dump all the configuration options in to the cwdir.
This was a bit more complicated to fix in a clean fashion, so I took to moving around code concerning user directories.
Instead of having GetUserPath serve a dual purpose of both getting and setting our user directories, break out to a new SetUserPath function.
GetUserPath will know only get the configured user path.
SetUserPath will set our user paths and setup the internal user path state.
This ending up being a lot cleaner overall, which is nice. Also less mind bending when attempting to read the code.
So now we won't dump all of our configuration in to the cwdir if ~/.dolphin-emu isn't found.
Fixes issue 8371.
The UI should decide on where it wants the user directory, not our core system.
This is in anticipation of some upcoming work on Android which will need proper user directory setting.
The libusb driver must be installed on the adapter (e.g. zadig can be used to install the driver in Windows). GameCube pad controllers are supported and will override the current input device assigned to the port. GameCube controller buttons are auto-configured and cannot be re-assigned. Rumble is supported. Hotplug is supported while playing a game. If a controller is unplugged from the adapter, Dolphin will fallback to using the host input device on that port. If a port on the adapter is unused, Dolphin will use the host input device for that port, allowing a mixture of host input devices and controllers connected to the adapter.
The adapter support can be disabled in the Controllers config if the OS driver is preferred (allowing the pad buttons to be reconfigured).
One adapter per system is supported.
