Reporting ACCIDENTAL_OVERRIDE on jvm signatures that have no descriptors

(marking them SYNTHETIC)

compiler/testData/diagnostics/testsWithStdLib/duplicateJvmSignature/platformStaticInObject.kt

@@ -0,0 +1,10 @@
+// !DIAGNOSTICS: -UNUSED_PARAMETER
+import kotlin.platform.platformStatic
+
+open class Base {
+    fun `foo$default`(i: Int, mask: Int) {}
+}
+
+object Derived : Base() {
+    <!ACCIDENTAL_OVERRIDE!>platformStatic fun foo(i: Int = 0)<!> {}
+}