[FIR/IR generator] Add kDoc property to AbstractElement & AbstractField

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

@@ -77,7 +77,9 @@ class Element(
 
     val generationCallback = config.generationCallback
     val propertyName = config.propertyName
-    val kDoc = config.kDoc
+
+    override val kDoc = config.kDoc
+
     val additionalImports: List<Import> = config.additionalImports
 
     override fun toString() = name
@@ -126,7 +128,9 @@ sealed class Field(
     abstract val transformable: Boolean
 
     val useInIrFactoryStrategy = config.useFieldInIrFactoryStrategy
-    val kdoc = config.kdoc
+    init {
+        kDoc = config.kdoc
+    }
 
     val printProperty = config.printProperty
     val generationCallback = config.generationCallback

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

@@ -70,7 +70,7 @@ fun printElements(generationPath: File, model: Model) = sequence {
                         addAnnotation(descriptorApiAnnotation)
                     }
 
-                    field.kdoc?.let {
+                    field.kDoc?.let {
                         addKdoc(it)
                     }