Ignore modules in perl-base in pman. pman shows the POD from modules, and takes the first in @INC. In Debian, the .pm files in perl-base have their POD documentation stripped away, and those are now first on @INC even when libperl5.30 are perl-modules-5.30 are installed (see #962138). As all .pm files in perl-base are also in the other packages, just ignore the pod-less ones in paths matchig perl-base.
