ath6kl: add full USB support

Now, with HTC pipe, it's possible to fully support USB version of AR6004.

Based on code by Kevin Fang.

Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
diff --git a/drivers/net/wireless/ath/ath6kl/debug.h b/drivers/net/wireless/ath/ath6kl/debug.h
index 1803a0b..49639d8 100644
--- a/drivers/net/wireless/ath/ath6kl/debug.h
+++ b/drivers/net/wireless/ath/ath6kl/debug.h
@@ -43,6 +43,7 @@
 	ATH6KL_DBG_WMI_DUMP	= BIT(19),
 	ATH6KL_DBG_SUSPEND	= BIT(20),
 	ATH6KL_DBG_USB		= BIT(21),
+	ATH6KL_DBG_USB_BULK	= BIT(22),
 	ATH6KL_DBG_ANY	        = 0xffffffff  /* enable all logs */
 };