Recent Changes to WITH_*/WITHOUT_* in src

Hey All,

It seems that the recent changes to the makefiles for building
world/kernel have broken some modifications I have locally for
implementing ASLR+PIE. I'm quite the bsd make newbie, so I thought I'd
ask for a bit of help. I'm sure the solution is quite simple.

My code is up on GitHub. I'll include links at the bottom of the email.

The code in question is in share/mk/bsd.prog.mk, where I'm checking to
see if MK_PIE is not equal to "no". Prior to the recent changes, this
code used to work. (Please note that I know that the way I'm cheking is
a bit bloated, if anyone has any suggestions to trim my code down, let
me know).

How this feature is supposed to work is:
1) PIE is added to the __DEFAULT_NO_OPTIONS to make building
applications as position-independent executables opt-in.
2) User adds WITH_PIE=1 to /etc/src.conf or /etc/make.conf
3) The application being built needs to also specify CAN_PIE=1 in its
Makefile. This is because some applications don't support being built as
a position-independent executable.
4) If MK_PIE is not "no" and CAN_PIE is defined, then add additional
CFLAGS.

The log from my build is here: http://ix.io/cf0

My code is here:
https://github.com/HardenedBSD/hardenedBSD/blob/hardened/current/aslr/share/mk/bsd.prog.mk#L14-L22

Thanks,

Shawn
CC: imp_at_bsdimp.com