HADOOP-15133. [JDK9] Ignore com.sun.javadoc.* and com.sun.tools.* in animal-sniffer-maven-plugin to compile with Java 9. (#4173)

(cherry picked from commit d2d8f4aeb3e214d1a96eeaf96bbe1e9301824ccd)

Contributed by Akira Ajisaka

hadoop-project/pom.xml

@@ -1597,6 +1597,8 @@
             <ignore>sun.misc.*</ignore>
             <ignore>sun.net.*</ignore>
             <ignore>sun.nio.ch.*</ignore>
+            <ignore>com.sun.javadoc.*</ignore>
+            <ignore>com.sun.tools.*</ignore>
           </ignores>
         </configuration>
       </plugin>