remove unused SuppressWarnings

Author: pan3793

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/service/launcher/IrqHandler.java

@@ -37,7 +37,6 @@
  */
 @InterfaceAudience.Private
 @InterfaceStability.Unstable
-@SuppressWarnings("UseOfSunClasses")
 public final class IrqHandler implements SignalUtil.Handler {
   private static final Logger LOG = LoggerFactory.getLogger(IrqHandler.class);