HDFS-12341. Ozone: maven dist compilation fails with "Duplicate classes found" error. Contributed by Mukul Kumar Singh.

hadoop-hdfs-project/hadoop-hdfs/pom.xml

@@ -168,11 +168,6 @@ http://maven.apache.org/xsd/maven-4.0.0.xsd">
       <artifactId>netty</artifactId>
       <scope>compile</scope>
     </dependency>
-    <dependency>
-      <groupId>io.netty</groupId>
-      <artifactId>netty-all</artifactId>
-      <scope>compile</scope>
-    </dependency>
     <dependency>
       <groupId>org.apache.htrace</groupId>
       <artifactId>htrace-core4</artifactId>