FIR: Add synthetic values/valueOf methods to Java classes

compiler/testData/loadJava/compiledJava/static/Enum.fir.txt

@@ -5,4 +5,10 @@ public final enum class Enum : R|kotlin/Enum<test/Enum>| {
 
     public final static field C: R|ft<test/Enum, test/Enum?>!|
 
+    public final static fun values(): R|kotlin/Array<test/Enum>| {
+    }
+
+    public final static fun valueOf(value: R|kotlin/String|): R|test/Enum| {
+    }
+
 }