C++: remove pointless predicate

cpp/ql/src/semmle/code/cpp/exprs/Expr.qll

@@ -1017,11 +1017,6 @@ class FoldExpr extends Expr, @foldexpr {
     this.isBinaryFold() and
     if this.isRightFold() then result = getChild(1) else result = getChild(0)
   }
-
-  /**
-   * Holds if this is a binary fold with a child expression representing the initial value.
-   */
-  predicate hasInitExpr() { exists(this.getInitExpr()) }
 }
 
 /**

cpp/ql/test/library-tests/fold/fold.ql

@@ -3,5 +3,5 @@ import cpp
 from FoldExpr fe, Expr pack, string init
 where
   pack = fe.getPackExpr() and
-  if fe.hasInitExpr() then init = fe.getInitExpr().toString() else init = "<no init>"
+  if exists(fe.getInitExpr()) then init = fe.getInitExpr().toString() else init = "<no init>"
 select fe, fe.getOperatorString(), pack, init