minor clean up wrt #2605 fix, for 2.11

Author: cowtowncoder

src/main/java/com/fasterxml/jackson/databind/JavaType.java

@@ -288,6 +288,14 @@ public boolean isConcrete() {
     @Override
     public boolean isArrayType() { return false; }
 
+    /**
+     * Method that basically does equivalent of:
+     *<pre>
+     *  Enum.class.isAssignableFrom(getRawClass())
+     *</pre>
+     * that is, return {@code true} if the underlying type erased class is {@code Enum}
+     * or one its subtypes (Enum implementations).
+     */
     @Override
     public final boolean isEnumType() {
         // 29-Sep-2019, tatu: `Class.isEnum()` not enough to detect custom subtypes.

src/main/java/com/fasterxml/jackson/databind/deser/DeserializerCache.java

@@ -367,7 +367,7 @@ protected JsonDeserializer<?> _createDeserializer2(DeserializationContext ctxt,
 
         // 12-Feb-20202, tatu: Need to ensure that not only all Enum implementations get
         //    there, but also `Enum` -- latter wrt [databind#2605], polymorphic usage
-        if (ClassUtil.isEnumType(type.getRawClass())) { // type.isEnumType()) {
+        if (type.isEnumType()) {
             return factory.createEnumDeserializer(ctxt, type, beanDesc);
         }
         if (type.isContainerType()) {