iwlagn: add an API to free the TX context

Tx free functions move to the transport layer. Unify the functions that deal with tx queues and cmd queue.

Since the CMD queue is not fully allocated, but uses the q->n_bd / q->window trick, the release flow of TX queue and CMD queue was different.
iwlagn_txq_free_tfd receives now the index of the TFD to be freed, which allows to unify the release flow for all the queues.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.h b/drivers/net/wireless/iwlwifi/iwl-agn.h
index 4351151..fabab0f 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.h
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.h
@@ -198,7 +198,8 @@
 void iwl_setup_rx_handlers(struct iwl_priv *priv);
 
 /* tx */
-void iwlagn_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq);
+void iwlagn_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq,
+				int index);
 int iwlagn_txq_attach_buf_to_tfd(struct iwl_priv *priv,
 				 struct iwl_tx_queue *txq,
 				 dma_addr_t addr, u16 len, u8 reset);
@@ -217,7 +218,6 @@
 void iwlagn_rx_reply_compressed_ba(struct iwl_priv *priv,
 				struct iwl_rx_mem_buffer *rxb);
 int iwlagn_tx_queue_reclaim(struct iwl_priv *priv, int txq_id, int index);
-void iwlagn_hw_txq_ctx_free(struct iwl_priv *priv);
 void iwlagn_txq_ctx_stop(struct iwl_priv *priv);
 
 static inline u32 iwl_tx_status_to_mac80211(u32 status)