fix WAW hazard handling

rocket/src/main/scala/dcache.scala

@@ -21,6 +21,7 @@ class ioDmem(view: List[String] = null) extends Bundle(view) {
   val resp_miss = Bool('output);
   val resp_nack = Bool('output);
   val resp_val  = Bool('output);
+  val resp_replay = Bool('output);
   val resp_data = Bits(64, 'output);
   val resp_data_subword = Bits(64, 'output);
   val resp_tag  = Bits(DCACHE_TAG_BITS, 'output);