Dropping package facades:

- light classes: do not generate light class for package facade
- drop package facades as multifile classes compilation mode support
- get rid of some additional package facade fqName usages
- update tests for light classes

compiler/tests/org/jetbrains/kotlin/codegen/CodegenTestUtil.java

@@ -68,7 +68,6 @@ public class CodegenTestUtil {
                 configuration.get(JVMConfigurationKeys.DISABLE_INLINE, false),
                 configuration.get(JVMConfigurationKeys.DISABLE_OPTIMIZATION, false),
                 /* useTypeTableInSerializer = */ false,
-                configuration.get(JVMConfigurationKeys.PACKAGE_FACADES_AS_MULTIFILE_CLASSES, false),
                 forExtraDiagnostics
         );
         KotlinCodegenFacade.compileCorrectFiles(state, CompilationErrorHandler.THROW_EXCEPTION);