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/inlineClasses/callableReferences/funWithInlineClassParameters.kt

@@ -14,7 +14,7 @@ value class S(val x: String)
 fun test(aZ: Z, aL: L, aS: S) = "${aZ.x} ${aL.x} ${aS.x}"
 
 fun box(): String {
-    if (::test.invoke(Z(1), L(1L), S("abc")) != "1 1 abc") throw AssertionError()
+    if (::test.let { it.invoke(Z(1), L(1L), S("abc")) } != "1 1 abc") throw AssertionError()
 
     return "OK"
 }