FIR: get rid of fictitious function symbols

compiler/fir/tree/src/org/jetbrains/kotlin/fir/symbols/impl/FictitiousFunctionSymbol.kt

@@ -1,21 +0,0 @@
-/*
- * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
- * that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.symbols.impl
-
-import org.jetbrains.kotlin.builtins.KotlinBuiltIns
-import org.jetbrains.kotlin.fir.symbols.ConeClassSymbol
-import org.jetbrains.kotlin.fir.symbols.ConeTypeParameterSymbol
-import org.jetbrains.kotlin.name.ClassId
-import org.jetbrains.kotlin.name.Name
-
-class FictitiousFunctionSymbol(className: Name, arity: Int) : ConeClassSymbol {
-    override val classId = ClassId(KotlinBuiltIns.BUILT_INS_PACKAGE_FQ_NAME, className)
-
-    class TypeParameterSymbol(index: Int) : ConeTypeParameterSymbol {
-        override val name: Name = Name.identifier("T$index")
-    }
-
-}