[Midnightbsd-cvs] mports: Makefile: Update the png shared lib version

[vganji at midnightbsd.org]

Log Message:
-----------
Update the png shared lib version

Modified Files:
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    mports/graphics/plotutils:
        Makefile (r1.3 -> r1.4)
        (http://cvsweb.midnightbsd.org/mports/graphics/plotutils/Makefile?r1=1.3&r2=1.4)