LSQ: Moved a couple of lines to enable O3 + Ruby

This patch makes O3 CPU work along with the Ruby memory model. Ruby
overwrites the senderState pointer with another pointer. The pointer
is restored only when Ruby gets done with the packet. LSQ makes use of
senderState just after sendTiming() returns. But the dynamic_cast returns
a NULL pointer since Ruby's senderState pointer is from a different class.
Storing the senderState pointer before calling sendTiming() does away with
the problem.

src/cpu/o3/lsq_unit_impl.hh

@@ -1191,10 +1191,10 @@ LSQUnit<Impl>::recvRetry()
         DPRINTF(LSQUnit, "Receiving retry: store blocked\n");
         assert(retryPkt != NULL);
 
-        if (dcachePort->sendTiming(retryPkt)) {
-            LSQSenderState *state =
-                dynamic_cast<LSQSenderState *>(retryPkt->senderState);
+        LSQSenderState *state =
+            dynamic_cast<LSQSenderState *>(retryPkt->senderState);
 
+        if (dcachePort->sendTiming(retryPkt)) {
             // Don't finish the store unless this is the last packet.
             if (!TheISA::HasUnalignedMemAcc || !state->pktToSend ||
                     state->pendingPacket == retryPkt) {