net: Add a helper to queue a buffer in a net_if instance

Makes code cleaner so it won't be necessary to access the net_if
internal queue directly.

Change-Id: I119a54e0639843093fa0da6f11e590e8990525d8
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>

include/net/yaip/net_if.h

@@ -193,6 +193,16 @@ static inline struct device *net_if_get_device(struct net_if *iface)
 	return iface->dev;
 }
 
+/**
+ * @brief Queue a packet into net if's TX queue
+ * @param iface Pointer to a network interface structure
+ * @param buf Pointer on a net buffer to queue
+ */
+static inline void net_if_queue_tx(struct net_if *iface, struct net_buf *buf)
+{
+	nano_fifo_put(&iface->tx_queue, buf);
+}
+
 /**
  * @brief Get an network interface's link address
  * @param iface Pointer to a network interface structure

net/yaip/net_core.c

@@ -380,7 +380,7 @@ int net_send_data(struct net_buf *buf)
 	}
 #endif
 
-	nano_fifo_put(&net_nbuf_iface(buf)->tx_queue, buf);
+	net_if_queue_tx(net_nbuf_iface(buf), buf);
 
 	return ret;
 }