cpu/esp32: add NETOPT_LINK_CONNECTED in esp_eth
cpu/esp32: add NETOPT_LINK_CONNECTED in esp_eth

Support for NETOPT_LINK_CONNECTED added to esp_eth_netdev::_get
mtausig/RIOT,yogo1212/RIOT,cladmi/RIOT,smlng/RIOT,RIOT-OS/RIOT,kaspar030/RIOT,aeneby/RIOT,basilfx/RIOT,kaspar030/RIOT,OlegHahm/RIOT,josephnoir/RIOT,rfuentess/RIOT,OlegHahm/RIOT,rfuentess/RIOT,x3ro/RIOT,jasonatran/RIOT,mtausig/RIOT,OTAkeys/RIOT,cladmi/RIOT,kYc0o/RIOT,smlng/RIOT,jasonatran/RIOT,authmillenon/RIOT,basilfx/RIOT,aeneby/RIOT,authmillenon/RIOT,OTAkeys/RIOT,smlng/RIOT,ant9000/RIOT,miri64/RIOT,authmillenon/RIOT,mtausig/RIOT,kaspar030/RIOT,miri64/RIOT,RIOT-OS/RIOT,RIOT-OS/RIOT,kaspar030/RIOT,RIOT-OS/RIOT,OlegHahm/RIOT,toonst/RIOT,jasonatran/RIOT,authmillenon/RIOT,rfuentess/RIOT,basilfx/RIOT,ant9000/RIOT,toonst/RIOT,kYc0o/RIOT,yogo1212/RIOT,x3ro/RIOT,x3ro/RIOT,toonst/RIOT,OTAkeys/RIOT,toonst/RIOT,OTAkeys/RIOT,basilfx/RIOT,authmillenon/RIOT,smlng/RIOT,basilfx/RIOT,josephnoir/RIOT,toonst/RIOT,rfuentess/RIOT,yogo1212/RIOT,kYc0o/RIOT,yogo1212/RIOT,yogo1212/RIOT,miri64/RIOT,OlegHahm/RIOT,OTAkeys/RIOT,ant9000/RIOT,OlegHahm/RIOT,aeneby/RIOT,kaspar030/RIOT,aeneby/RIOT,mtausig/RIOT,yogo1212/RIOT,josephnoir/RIOT,x3ro/RIOT,mtausig/RIOT,kYc0o/RIOT,cladmi/RIOT,miri64/RIOT,RIOT-OS/RIOT,josephnoir/RIOT,ant9000/RIOT,rfuentess/RIOT,smlng/RIOT,jasonatran/RIOT,josephnoir/RIOT,miri64/RIOT,ant9000/RIOT,kYc0o/RIOT,jasonatran/RIOT,cladmi/RIOT,authmillenon/RIOT,x3ro/RIOT,aeneby/RIOT,cladmi/RIOT