don't explicitly configure the last round of packages

don't explicitly configure the last round of packages

We end our operation by calling "dpkg --configure -a", so instead of
running a (big) configure run with all packages mentioned explicitly
before this, we simply skip them and let them be handled by this call
implicitly.

There isn't really an observeable gain to be had here from a speed
point, but it helps in avoiding an (uncommon) problem of having a too
long commandline passed to dpkg, which we would split up (probably
incorrectly).