"make install" unnecessarily creates certain directories
etc/ is not necessary since 2009, when we started
bind.keys. That being said, IMHO it was unnecessary even
before, but oh well.
var/ is not necessary since 2008, which is when
named_os_openfile() started calling
The bottom line is that neither of these directories should be created
make install these days. I would fix it in v9.16 and leave
~"v9.11" alone, this is nothing critical.