Use typedef'ed `pkg_config_t' in for (struct pkg_config).type
Small code refactoring to avoid too many condition branches.
Set a default return code value for meta_dirrm().

scan-build reported that `ret' might be returned unset. It has been
defaulted to EPKG_OK, as EPKG_FATAL seems to be reported conditionnaly
when lstat(2).
Refactored the file() function as was meta_dirrm().

see b5fb041 and 17ce89e.