iwlagn: provide heplers to access the transport ops

This removes the for priv->trans.ops->...

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-trans.c b/drivers/net/wireless/iwlwifi/iwl-trans.c
index 0c92456..d760857 100644
--- a/drivers/net/wireless/iwlwifi/iwl-trans.c
+++ b/drivers/net/wireless/iwlwifi/iwl-trans.c
@@ -467,7 +467,7 @@
 	return 0;
 
 error:
-	priv->trans.ops->tx_free(priv);
+	trans_tx_free(priv);
 
 	return ret;
 }
@@ -511,7 +511,7 @@
 error:
 	/*Upon error, free only if we allocated something */
 	if (alloc)
-		priv->trans.ops->tx_free(priv);
+		trans_tx_free(priv);
 	return ret;
 }