Do not check from duplicate when loading from manifest considering the manifest for files has been produced by pkgng, and thus is clean.
Do not check from duplicate when loading from manifest considering the manifest
for files has been produced by pkgng, and thus is clean.

This speed up pkg repo, and pkg install

Fixes #322

Reported by:	ohauer
Tested by:	ohauer

skoef/pkg,khorben/pkg,en90/pkg,skoef/pkg,khorben/pkg,Open343/pkg,en90/pkg,Open343/pkg,khorben/pkg,junovitch/pkg,junovitch/pkg