[ONOS-3737] Bump up checkstyle version from 2.16 to 2.17 with some compilation fixes

Change-Id: I3ade52ff15b3114f5748ab3151c02c8c74af38f0
diff --git a/utils/misc/src/main/java/org/onlab/packet/pim/PIMHelloOption.java b/utils/misc/src/main/java/org/onlab/packet/pim/PIMHelloOption.java
index 1ea0ba8..7d05d92 100644
--- a/utils/misc/src/main/java/org/onlab/packet/pim/PIMHelloOption.java
+++ b/utils/misc/src/main/java/org/onlab/packet/pim/PIMHelloOption.java
@@ -131,7 +131,7 @@
         return opt;
     }
 
-    public byte [] serialize() {
+    public byte[] serialize() {
         int len = 4 + this.optLength;
         ByteBuffer bb = ByteBuffer.allocate(len);
         bb.putShort(this.optType);