Log Message:
I forgot to commit this with the new patches yesterday!!!
Many thanks to Chris Gilbert for noticing it.

Bump PKGREVISION
- Add dependency on autoconf and have auto{header,conf} run at pre-configure
  stage: this is need to avoid conflict between the distribution patch file for
  IPv6 and patch files.
- Pave the way for the removal of PERL5_GENERATE_PLIST from bsd.pkg.mk:
  use perl5/module.mk with PERL5_CONFIGURE=NO.
- Ensure relocatable objects are created so that when the Perl modules are
  linked they are composed wholly from relocatable objects.
  We query perl for how to compile a source file into a relocatable object file.
  Thanks again jlam for this.