Kindle: Make sure Device:untar actually works
Kindle: Make sure Device:untar actually works

The fuse proxy strikes again... Fix #9704

poire-z/koreader,Frenzie/koreader,NiLuJe/koreader,poire-z/koreader,koreader/koreader,Frenzie/koreader,NiLuJe/koreader,koreader/koreader