JVM: generate 'Deprecated' on method as runtime-visible annotation

We generate @java.lang.Deprecated annotation on methods of $DefaultImpls
classes in compatibility mode. This annotation has RUNTIME retention and
should be visible.

Also, get rid of representing annotations as Class'es (yes we know that
these annotations are in compiler CLASSPATH, but we should not rely on
such classes and associated information).

compiler/testData/codegen/box/jvm8/defaults/compatibility/deprecatedAnnotation.kt

@@ -0,0 +1,20 @@
+// !JVM_DEFAULT_MODE: compatibility
+// TARGET_BACKEND: JVM
+// JVM_TARGET: 1.8
+// FULL_JDK
+// WITH_RUNTIME
+
+interface IFoo {
+    @JvmDefault
+    fun foo() {}
+}
+
+fun box(): String {
+    val iFoo = IFoo::class.java
+    val iFooDefaultImpls = Class.forName("${iFoo.name}\$DefaultImpls")
+    val fooMethod = iFooDefaultImpls.declaredMethods.find { it.name == "foo" }
+        ?: throw AssertionError("No method 'foo' in class ${iFooDefaultImpls.name}")
+    fooMethod.getAnnotation(java.lang.Deprecated::class.java)
+        ?: throw AssertionError("No java.lang.Deprecated annotation on method 'foo'")
+    return "OK"
+}