Setting preferred directories result in a ~/.gvba/config files with correct values,
but saves are not created under the directory expected(~/.gvba/ in my case),
they are created in the same directory as the ROM instead.
Oddly enough, screenshots are correctly created in the right directory(~/.gvba/ in my case).
When executing `vba` instead of `gvba`, saves are created under ~/.vba/ directory.