tilelink: make bus xbar protected so it can be suggestNamed

src/main/scala/coreplex/PeripheryBus.scala

@@ -22,6 +22,8 @@ case class PeripheryBusParams(
 case object PeripheryBusParams extends Field[PeripheryBusParams]
 
 class PeripheryBus(params: PeripheryBusParams)(implicit p: Parameters) extends TLBusWrapper(params) {
+  xbar.suggestName("PeripheryBus")
+
   def toFixedWidthSingleBeatSlave(widthBytes: Int) = {
     TLFragmenter(widthBytes, params.blockBytes)(outwardWWNode)
   }