log uncaught Exception

- Use execute instead of submit so that uncaught Exception will
  be dealt and logged by ExecutorService's handler.
- Use component's own logger

Change-Id: I761264aea00748980929b5048e111756776dd2f6
diff --git a/providers/lldp/src/main/java/org/onosproject/provider/lldp/impl/LldpLinkProvider.java b/providers/lldp/src/main/java/org/onosproject/provider/lldp/impl/LldpLinkProvider.java
index b477634..6ff437a 100644
--- a/providers/lldp/src/main/java/org/onosproject/provider/lldp/impl/LldpLinkProvider.java
+++ b/providers/lldp/src/main/java/org/onosproject/provider/lldp/impl/LldpLinkProvider.java
@@ -338,7 +338,7 @@
 
         loadDevices();
 
-        executor = newSingleThreadScheduledExecutor(groupedThreads("onos/link", "discovery-%d"));
+        executor = newSingleThreadScheduledExecutor(groupedThreads("onos/link", "discovery-%d", log));
         executor.scheduleAtFixedRate(new SyncDeviceInfoTask(),
                                      DEVICE_SYNC_DELAY, DEVICE_SYNC_DELAY, SECONDS);
         executor.scheduleAtFixedRate(new LinkPrunerTask(),