Factor out duplicated mangling logic for functions into the base class

^KT-57777 Fixed
^KT-57818 Fixed

compiler/testData/ir/irText/declarations/parameters/defaultPropertyAccessors.kt

@@ -1,6 +1,6 @@
 // FIR_IDENTICAL
 
-// MUTE_SIGNATURE_COMPARISON_K2: ANY
+// MUTE_SIGNATURE_COMPARISON_K2: JVM_IR
 // ^ KT-57429
 
 val test1 = 42

compiler/testData/ir/irText/declarations/parameters/lambdas.kt

@@ -1,7 +1,3 @@
-// MUTE_SIGNATURE_COMPARISON_K2: JS_IR
-// MUTE_SIGNATURE_COMPARISON_K2: NATIVE
-// ^ KT-57818
-
 val test1 : (String) -> String = { it }
 val test2 : Any.(Any) -> Any = { it.hashCode() }
 val test3 = { i: Int, j: Int -> }

compiler/testData/ir/irText/declarations/parameters/propertyAccessors.kt

@@ -1,8 +1,5 @@
 // FIR_IDENTICAL
 
-// MUTE_SIGNATURE_COMPARISON_K2: JS_IR
-// ^ KT-57818
-
 val test1 get() = 42
 
 var test2 get() = 42; set(value) {}

compiler/testData/ir/irText/declarations/parameters/typeParameterBeforeBound.kt

@@ -1,8 +1,5 @@
 // FIR_IDENTICAL
 
-// MUTE_SIGNATURE_COMPARISON_K2: JS_IR
-// ^ KT-57818
-
 class Test1<T : U, U>
 
 fun <T : U, U> test2() {}