[FIR]: fix library methods in packages

Library methods such as 'listOf' are resolved
to have the package fragments as their parents,
but JVM expects their containing file classes as parents.
This fix generates those file classes and
uses them as parent replacements for such library methods.

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

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND_FIR: JVM_IR
 // WITH_RUNTIME
 // WITH_REFLECT