JVM IR: Avoid direct invokes in callable reference tests

Due to the direct invoke optimization, most callable reference tests
were not generating callable references/lambdas.

compiler/testData/codegen/box/callableReference/function/innerConstructorFromClass.kt

@@ -4,7 +4,7 @@ class A {
         val k = 222
     }
     
-    fun result() = (A::Inner)(this).o + (A::Inner)(this).k
+    fun result() = (A::Inner).let { it(this) }.o + (A::Inner).let { it(this) }.k
 }
 
 fun box(): String {