There were too many checks for whether we had rst2man in the
Makefile.am files, leading us to not install files properly if rst2man
was not available.  Fix this.


git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@5462 d4fa192b-c00b-0410-8231-f00ffab90ce4