[Midnightbsd-cvs] mports: Makefile: Fix the Shared lib version for png

[vganji at midnightbsd.org]

Log Message:
-----------
Fix the Shared lib version for png

Modified Files:
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    mports/print/ghostscript-gpl:
        Makefile (r1.15 -> r1.16)
        (http://cvsweb.midnightbsd.org/mports/print/ghostscript-gpl/Makefile?r1=1.15&r2=1.16)