IR: make IrTypeOperatorCall.typeOperand mutable

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/expressions/IrTypeOperatorCall.kt

@@ -69,6 +69,6 @@ enum class IrTypeOperator {
 abstract class IrTypeOperatorCall : IrExpression() {
     abstract val operator: IrTypeOperator
     abstract var argument: IrExpression
-    abstract val typeOperand: IrType
+    abstract var typeOperand: IrType
     abstract val typeOperandClassifier: IrClassifierSymbol
 }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/expressions/impl/IrTypeOperatorCallImpl.kt

@@ -30,7 +30,7 @@ class IrTypeOperatorCallImpl(
     override val endOffset: Int,
     override var type: IrType,
     override val operator: IrTypeOperator,
-    override val typeOperand: IrType,
+    override var typeOperand: IrType,
     override var argument: IrExpression,
 ) : IrTypeOperatorCall() {
     override val typeOperandClassifier: IrClassifierSymbol