Register Ethernet `netif` in WiFiGeneric to (#7632)

Co-authored-by: Me No Dev <me-no-dev@users.noreply.github.com>

libraries/Ethernet/src/ETH.cpp

@@ -41,6 +41,7 @@
 #include "lwip/dns.h"
 
 extern void tcpipInit();
+extern void add_esp_interface_netif(esp_interface_t interface, esp_netif_t* esp_netif); /* from WiFiGeneric */
 
 #if ESP_IDF_VERSION_MAJOR > 3
 
@@ -327,6 +328,9 @@ bool ETHClass::begin(uint8_t phy_addr, int power, int mdc, int mdio, eth_phy_typ
         return false;
     }
 
+    /* attach to WiFiGeneric to receive events */
+    add_esp_interface_netif(ESP_IF_ETH, eth_netif);
+
     if(esp_eth_start(eth_handle) != ESP_OK){
         log_e("esp_eth_start failed");
         return false;