Xorg access is broken if there are several entries in `xauth list`

[cizra]

Apparently I must have used SSH xorg forwarding from another machine, as I had several entries in xauth list. playonlutris picked the wrong one. I worked around by xauth removeing the obsolete ones, so I ended up with only the correct one. It'd be nicer to somehow autodetect the correct one (for example $(hostname)/unix$DISPLAY or such). Failing that, it'd at least make sense to fail if there are multiple entries, rather than choose the wrong entry.