[CFT/RFC]: refactor bsd.prog.mk to understand multiple programs instead of a singular program

[Simon J. Gerraty]

On Fri, 26 Oct 2012 08:27:06 -0600, Warner Losh writes:
>And we've had the :U and :L for a similar period of time as well.  =

Sorry, I didn't mean to imply age has anything to do with it.
The doc I refered to makes it clear that the two sets of conflicting
modifers were introduced at about the same time.

>Why can't there be a make target that turns them on in FreeBSD compat =
>mode.  You could then just drop those into bsd.port.mk and be done with =

Because then you would lose the functionality that the alternative
modifiers provide.  Imagine throwing away the ability in /bin/sh to do
${foo:-bar}
Also it would perpetuate the divergence in syntax for little reason.

BTW there are currently < 300 makefiles in ports/ affected by the
transition to bmake, and there were an even smaller number in src/.