[IR generator] Add missing isChild = false

Those fields were effectively marked as child elements after refactor.
However, because of the current (to possibly be changed) configuration,
the generator did not write accept methods for them.

compiler/ir/ir.tree/tree-generator/src/org/jetbrains/kotlin/ir/generator/IrTree.kt

@@ -860,8 +860,8 @@ object IrTree : AbstractTreeBuilder() {
 
         visitorParameterName = "inlinedBlock"
 
-        +field("inlineCall", functionAccessExpression)
-        +field("inlinedElement", rootElement)
+        +field("inlineCall", functionAccessExpression, isChild = false)
+        +field("inlinedElement", rootElement, isChild = false)
     }
     val syntheticBody: Element by element(Expression) {
         visitorParameterName = "body"