Bug#439947: live-helper: lh_clean silently ignores additional non-option arguments

[jpryzby+lhbzpo at quoininc.com (Justin Pryzby)]

Package: live-helper
Version: 1.0~a23-1

"lh_clean binary chroot" doesn't clean the chroot, but only the image.
It should either check that there's exactly one non-option argument,
or process all of them.