Replaced another log.Printf

(in a file I hadn't noticed)

server/if_utils.go

@@ -2,7 +2,6 @@ package weavedns
 
 import (
 	"fmt"
-	"log"
 	"net"
 	"time"
 )
@@ -12,13 +11,13 @@ func EnsureInterface(ifaceName string, wait int) (iface *net.Interface, err erro
 	if err == nil || wait == 0 {
 		return
 	}
-	log.Println("Waiting for interface", ifaceName, "to come up")
+	Info.Println("Waiting for interface", ifaceName, "to come up")
 	for ; err != nil && wait > 0; wait -= 1 {
 		time.Sleep(1 * time.Second)
 		iface, err = findInterface(ifaceName)
 	}
 	if err == nil {
-		log.Println("Interface", ifaceName, "is up")
+		Info.Println("Interface", ifaceName, "is up")
 	}
 	return
 }