uanble to copy files via kde dolphin

[maz-1]

Error message: "There is not enough space on the disk to write file:///<file_path>
run cp from commandline works

[maz-1]

maz-1@e229325
Add statfs support that reports alot of free space solves the problem
Maybe try to get meaningful values from toybox df on client side later.

[bcegkmqs23]

This works. Hope there can be a PR and it can be merged.