Fix SONAR issue - mutable public variables

Change-Id: Ic6189c14c7976ab3cb664ddc2fc6fb28103f9c7a
diff --git a/app/src/main/java/org/onosproject/segmentrouting/pwaas/PwaasUtil.java b/app/src/main/java/org/onosproject/segmentrouting/pwaas/PwaasUtil.java
index fa2807e..9a7c749 100644
--- a/app/src/main/java/org/onosproject/segmentrouting/pwaas/PwaasUtil.java
+++ b/app/src/main/java/org/onosproject/segmentrouting/pwaas/PwaasUtil.java
@@ -43,10 +43,10 @@
     private static final Logger log = LoggerFactory.getLogger(PwaasUtil.class);
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    public static DeviceService deviceService = AbstractShellCommand.get(DeviceService.class);;
+    private static DeviceService deviceService = AbstractShellCommand.get(DeviceService.class);;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    public static InterfaceService intfService = AbstractShellCommand.get(InterfaceService.class);
+    private static InterfaceService intfService = AbstractShellCommand.get(InterfaceService.class);
 
     private PwaasUtil() {
         return;