restore javadoc references for non-phisical methods, e.g. enum#valueOf

IDEA-187289
looks like there is no fields which can be generated, so only methods are checked through processDeclarations

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/javaDoc/Foo.java

@@ -0,0 +1,7 @@
+/**
+ * @see Foo#valueOf(String) 
+ */
+public enum Foo {
+    
+    A, B, C
+}