Merge pull request #5745 from kjbracey-arm/k64f_init_order

K64F Ethernet: avoid using NULL thread during init

Author: 0xc0170

features/FEATURE_LWIP/lwip-interface/lwip-eth/arch/TARGET_Freescale/k64f_emac.c

@@ -140,7 +140,9 @@ static void k64f_tx_reclaim(struct k64f_enetdata *k64f_enet)
  */
 void enet_mac_rx_isr()
 {
-    osThreadFlagsSet(k64f_enetdata.thread, FLAG_RX);
+    if (k64f_enetdata.thread) {
+        osThreadFlagsSet(k64f_enetdata.thread, FLAG_RX);
+    }
 }
 
 void enet_mac_tx_isr()
@@ -756,6 +758,9 @@ err_t eth_arch_enetif_init(struct netif *netif)
   /* Worker thread */
   k64f_enetdata.thread = sys_thread_new("k64f_emac_thread", emac_thread, netif->state, THREAD_STACKSIZE, THREAD_PRIORITY)->id;
 
+  /* Trigger thread to deal with any RX packets that arrived before thread was started */
+  enet_mac_rx_isr();
+
   return ERR_OK;
 }