Fix class new with math.

src/V3Width.cpp

@@ -3113,7 +3113,6 @@ private:
                 "Illegal to call 'new' using an abstract virtual class (IEEE 1800-2017 8.21)");
         }
         userIterate(nodep->taskp(), nullptr);
-        userIterateChildren(nodep, nullptr);
         processFTaskRefArgs(nodep);
     }
     virtual void visit(AstNewCopy* nodep) override {

test_regress/t/t_class_new.v

@@ -29,7 +29,7 @@ module t (/*AUTOARG*/);
       c1 = new;
       if (c1.imembera != 5) $stop;
 
-      c2 = new(2);
+      c2 = new(3 - 1);
       if (c2.imembera != 3) $stop;
       if (c2.geta() != 3) $stop;