Add debug logging of add/remove operations in flow rule store

Change-Id: Ib8bd911f223898cbbaf64304ad3307dae450838e
(cherry picked from commit f51293466d1cde735b3b11a7b5e18b3602c52c86)
diff --git a/core/store/dist/src/main/java/org/onosproject/store/flow/impl/ECFlowRuleStore.java b/core/store/dist/src/main/java/org/onosproject/store/flow/impl/ECFlowRuleStore.java
index ceaf12e..d21984a 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/flow/impl/ECFlowRuleStore.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/flow/impl/ECFlowRuleStore.java
@@ -510,10 +510,12 @@
                 switch (op.operator()) {
                     case ADD:
                         entry = new DefaultFlowEntry(op.target());
+                        log.debug("Adding flow rule: {}", entry);
                         flowTable.add(entry);
                         return op;
                     case MODIFY:
                         entry = new DefaultFlowEntry(op.target());
+                        log.debug("Updating flow rule: {}", entry);
                         flowTable.update(entry);
                         return op;
                     case REMOVE:
@@ -622,6 +624,7 @@
     private FlowRuleEvent removeFlowRuleInternal(FlowEntry rule) {
         // This is where one could mark a rule as removed and still keep it in the store.
         final FlowEntry removed = flowTable.remove(rule);
+        log.debug("Removed flow rule: {}", removed);
         // rule may be partial rule that is missing treatment, we should use rule from store instead
         return removed != null ? new FlowRuleEvent(RULE_REMOVED, removed) : null;
     }