Properly report diagnostics on platformStatic annotations

#KT-6937 Fixed

compiler/testData/diagnostics/testsWithStdLib/annotations/platformStatic/finalAndAbstract.kt

@@ -0,0 +1,35 @@
+// !DIAGNOSTICS: -UNUSED_VARIABLE
+import kotlin.platform.platformStatic
+
+abstract class A {
+
+    open fun a() {}
+
+    abstract fun b()
+
+    open fun c() {}
+}
+
+object B: A() {
+
+    <!OVERRIDE_CANNOT_BE_STATIC!>[platformStatic] override fun a()<!> {}
+
+    <!OVERRIDE_CANNOT_BE_STATIC!>[platformStatic] override fun b()<!> {}
+
+    <!OVERRIDE_CANNOT_BE_STATIC!>[platformStatic] final override fun c()<!> {}
+
+    [platformStatic] open fun d() {}
+}
+
+class C {
+
+    default object: A() {
+        [platformStatic] override fun a() {}
+
+        [platformStatic] override fun b() {}
+
+        [platformStatic] final override fun c() {}
+
+        [platformStatic] open fun d() {}
+    }
+}