hg: shenandoah/jdk10/hotspot: remove useless code following 8176506

[rwestrel at redhat.com]

Changeset: b04cfcf830ec
Author:    roland
Date:      2017-07-26 10:30 +0200
URL:       http://hg.openjdk.java.net/shenandoah/jdk10/hotspot/rev/b04cfcf830ec

remove useless code following 8176506

! src/share/vm/opto/addnode.cpp