to use ``.if defined()'' inside bsd.own.mk to test for defines
in individual makefiles. For example, setting DEBUG_FLAGS in
Makefile didn't take the desired effect on the STRIP assignment.
Added bsd.init.mk (like in NetBSD) that handles the inclusion
of ../Makefile.inc and bsd.own.mk from all bsd.*.mk files that
"build something".
Back out bsd.own.mk,v 1.15: moved OBJFORMAT initialization back
to sys.mk (several source tree makefiles want to check it early)
and removed MACHINE_ARCH initialization (it's hard to see from
looking at the commitlogs what the problem was at the time, but
now it serves no purpose).
Prohibit the direct inclusion of bsd.man.mk and bsd.libnames.mk.
Protect bsd.obj.mk from repetitive inclusion. Prohibiting the
direct inclusion of bsd.obj.mk might be a good idea too.
