rt2x00: Fix tx status handling in rt2800pci

The patches "rt2x00: Improve TX status entry validation" and "rt2x00: rework tx
status handling in rt2800pci" together were causing problems with tx status
processing in rt2800pci:

phy1 -> rt2800pci_txdone: Warning - Got TX status for an empty queue 3, dropping
phy1 -> rt2800pci_txdone: Warning - Got TX status for an unavailable queue 7, dropping

Fix this by using the correct field definition for getting the QID out of the
tx status report.

Reported-by: Luis Correia <luis.f.correia@gmail.com>
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Tested-by: Luis Correia <luis.f.correia@gmail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rt2x00/rt2800pci.c

@@ -676,7 +676,7 @@ static void rt2800pci_txdone(struct rt2x00_dev *rt2x00dev)
 			break;
 		}
 
-		qid = rt2x00_get_field32(status, TX_STA_FIFO_PID_TYPE) - 1;
+		qid = rt2x00_get_field32(status, TX_STA_FIFO_PID_QUEUE);
 		if (qid >= QID_RX) {
 			/*
 			 * Unknown queue, this shouldn't happen. Just drop