FirSupertypesChecker: implement six more diagnostics

compiler/fir/analysis-tests/testData/resolveWithStdlib/multiModule/MemberType.fir.txt

@@ -19,7 +19,7 @@ FILE: common.kt
     }
 Module: m1-jvm
 FILE: jvm.kt
-    public final actual class MyList : R|kotlin/Any| {
+    public open actual class MyList : R|kotlin/Any| {
         public constructor(): R|MyList| {
             super<R|kotlin/Any|>()
         }

compiler/fir/analysis-tests/testData/resolveWithStdlib/multiModule/MemberType.kt

@@ -11,7 +11,7 @@ open class Wrapper(val list: MyList)
 // MODULE: m1-jvm(m1-common)
 // FILE: jvm.kt
 
-actual class MyList {
+actual open class MyList {
     actual fun get(i: Int): Int = i
 
     fun set(i: Int, v: Int) {}

compiler/fir/analysis-tests/testData/resolveWithStdlib/problems.fir.txt

@@ -38,7 +38,7 @@ FILE: problems.kt
         public get(): R|kotlin/String|
     public final val p: R|kotlin/Pair<kotlin/Int, kotlin/String>| = R|kotlin/Pair.Pair|<R|kotlin/Int|, R|kotlin/String|>(Int(0), String())
         public get(): R|kotlin/Pair<kotlin/Int, kotlin/String>|
-    public final class Base<T> : R|kotlin/Any| {
+    public open class Base<T> : R|kotlin/Any| {
         public constructor<T>(x: R|T|): R|Base<T>| {
             super<R|kotlin/Any|>()
         }

compiler/fir/analysis-tests/testData/resolveWithStdlib/problems.kt

@@ -17,7 +17,7 @@ val String.bar get() = "987"
 
 val p = Pair(0, "")
 
-class Base<T>(val x: T)
+open class Base<T>(val x: T)
 class Derived : Base<Int>(10)
 val xx = Derived().x + 1