Fix IllegalAccessException on private annotation in reflection

#KT-14094 Fixed

compiler/testData/codegen/box/reflection/annotations/privateAnnotation.kt

@@ -0,0 +1,14 @@
+// IGNORE_BACKEND: JS, NATIVE
+// WITH_REFLECT
+
+annotation private class Ann(val name: String)
+
+class A {
+    @Ann("OK")
+    fun foo() {}
+}
+
+fun box(): String {
+    val ann = A::class.members.single { it.name == "foo" }.annotations.single() as Ann
+    return ann.name
+}