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>

drivers/net/wireless/ath/ath6kl/debug.h

@@ -43,6 +43,7 @@ enum ATH6K_DEBUG_MASK {
 	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 */
 };