ath9k: Fix the 'xmit' debugfs file

The 'xmit' debugfs file has become big and unwieldy, fix
multiple issues with its usage:

* Store TX counters/statistics only for the 4 Access Categories.
  Use IEEE80211_NUM_ACS instead of ATH9K_NUM_TX_QUEUES.

* Move various utility macros to debug.h, they can be reused
  elsewhere.

* Remove tx_complete_poll_work_seen.

* Remove code that accesses various internal queue-specific
  variables without any locking whatsoever. HW/SW queue details
  will be handled in a subsequent patch.

* Do not print internal values like txq_headidx and txq_headidx.
  They were mostly unused anyway, considering code like:
  PRX("txq_tailidx:     ", txq_headidx);

* Handle 'txprocdesc' for EDMA too.

Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index ae7f289..3413094 100644
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -2319,6 +2319,8 @@
 
 		ath_txq_lock(sc, txq);
 
+		TX_STAT_INC(txq->axq_qnum, txprocdesc);
+
 		if (list_empty(&txq->txq_fifo[txq->txq_tailidx])) {
 			ath_txq_unlock(sc, txq);
 			return;