[Midnightbsd-cvs] mports: Makefile: re-add os check

[laffer1 at midnightbsd.org]

Log Message:
-----------
re-add os check

Modified Files:
--------------
    mports/net/mDNSResponder:
        Makefile (r1.8 -> r1.9)
        (http://cvsweb.midnightbsd.org/mports/net/mDNSResponder/Makefile?r1=1.8&r2=1.9)