[Midnightbsd-cvs] src: Makefile: Don't use ?= unnecessarily

[laffer1 at midnightbsd.org]

Log Message:
-----------
Don't use ?= unnecessarily

Modified Files:
--------------
    src/sys:
        Makefile (r1.11 -> r1.12)
        (http://cvsweb.midnightbsd.org/src/sys/Makefile?r1=1.11&r2=1.12)