Remove '<apt-pkg/debfile.h>' header
They seem to be causing issues when linking on Ubuntu 18.04 for some reason. Calling pkgCacheFile->BuildCaches
seems to have the same effect as the manual checking that was in place previously.
See https://drone.hunterwittenborn.com/makedeb/makedeb/707/4/2 for an example of where this is happening.
Edited by Hunter Wittenborn