I'm planning on enabling IPv6 support in boot floppies.
	(grabbing tar.gz via IPv6 and such)

	To do this, I will need to have INET6-enabled ifconfig into boot
	floppies.  Which route should I take?
	- add -DINET6 into distrib/utils/x_ifconfig/Makefile.
	  this would increase ifconfig binary size by 6K (i386, after
	  stripping).
>-rw-r--r--  1 itojun  wheel  147340 Dec 31 11:55 /tmp/ifconfig.inet4
>-rwxr-xr-x  1 itojun  wheel  153056 Dec 31 11:55 /tmp/ifconfig.inet46
	- make separate x_ifconfig6 (or some other name) with -DINET_ONLY
	  -DINET.  use x_ifconfig6/ifconfig as necessary.

	I prefer former as it is much simpler, and will save us from
	thinking about consistency between x_ifconfig and x_ifconfig6.

itojun