node: Log local boot ID

We have very little logging of the boot IDs. Really fixing that will
require a bit of work to not be too verbose, but in the meantime, we
should at least log the local boot ID.

Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>

pkg/node/bootid.go

@@ -3,8 +3,16 @@
 
 package node
 
-var localBootID string
+import "sync"
+
+var (
+	localBootID string
+	logOnce     sync.Once
+)
 
 func GetBootID() string {
+	logOnce.Do(func() {
+		log.Infof("Local boot ID is %q", localBootID)
+	})
 	return localBootID
 }