KT-8273 Don't mark serialVersionUID as unused

#KT-8273 fixed

idea/testData/inspections/unusedSymbol/property/serialVersionUid.kt

@@ -0,0 +1,13 @@
+// FULL_JDK
+
+import kotlin.platform.platformStatic
+
+class Klass : java.io.Serializable {
+    companion object {
+        private platformStatic val serialVersionUID: Long = 239
+    }
+}
+
+fun main(args: Array<String>) {
+    Klass()
+}