Introduce UNUSED_ANONYMOUS_PARAMETER for anonymous functions

It is not reported for 1.0 language version because
renaming to _ is not possible. It has weak warning severity

So #KT-8813 Fixed
So #KT-16875 Fixed

compiler/testData/diagnostics/tests/controlFlowAnalysis/unusedInAnonymous.txt

@@ -0,0 +1,4 @@
+package
+
+public fun someApi(/*0*/ f: (kotlin.Int) -> kotlin.Unit): kotlin.Unit
+public fun test(): kotlin.Unit