Since rmind cleaned up sys/fd_set.h last winter, sys/types.h no longer

Since rmind cleaned up sys/fd_set.h last winter, sys/types.h no longer
exposes howmany(). This is generally a good thing, but as a result
libxview fails to find it, so it turns up as a missing external
function instead. Due to the wonders of ELF libs, combined with help
from imake, this results in a broken libxview that nothing else can
successfully link with. So, patch it up. PKGREVISION -> 9.