Create an empty package iterator when we don't know about the given file.
This is an easy way to stop segfaults when trying to destroy iterators for
unknown files.
1 ## Process this file with automake to produce Makefile.in
3 pkgconfigdir = $(libdir)/pkgconfig
4 pkgconfig_DATA = razor.pc
6 bashcompletiondir = ${SYSCONFDIR}/bash_completion.d
7 dist_bashcompletion_DATA = razor.sh