cpu/esp8266: send timeout handling in esp_wifi
cpu/esp8266: send timeout handling in esp_wifi

A timeout was introduced if sending a frame takes to long time. In that case the WiFi interface disconnects and reconnects automatically to recover.
x3ro/RIOT,authmillenon/RIOT,ant9000/RIOT,OlegHahm/RIOT,josephnoir/RIOT,x3ro/RIOT,basilfx/RIOT,cladmi/RIOT,rfuentess/RIOT,aeneby/RIOT,smlng/RIOT,BytesGalore/RIOT,mfrey/RIOT,aeneby/RIOT,lazytech-org/RIOT,OTAkeys/RIOT,rfuentess/RIOT,yogo1212/RIOT,basilfx/RIOT,lazytech-org/RIOT,OTAkeys/RIOT,OlegHahm/RIOT,basilfx/RIOT,A-Paul/RIOT,jasonatran/RIOT,basilfx/RIOT,authmillenon/RIOT,ant9000/RIOT,OlegHahm/RIOT,mtausig/RIOT,lazytech-org/RIOT,rfuentess/RIOT,OlegHahm/RIOT,x3ro/RIOT,BytesGalore/RIOT,toonst/RIOT,ant9000/RIOT,kaspar030/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,x3ro/RIOT,RIOT-OS/RIOT,miri64/RIOT,ant9000/RIOT,OTAkeys/RIOT,cladmi/RIOT,smlng/RIOT,jasonatran/RIOT,kaspar030/RIOT,x3ro/RIOT,jasonatran/RIOT,toonst/RIOT,toonst/RIOT,cladmi/RIOT,miri64/RIOT,smlng/RIOT,yogo1212/RIOT,yogo1212/RIOT,A-Paul/RIOT,yogo1212/RIOT,rfuentess/RIOT,cladmi/RIOT,BytesGalore/RIOT,josephnoir/RIOT,smlng/RIOT,yogo1212/RIOT,ant9000/RIOT,toonst/RIOT,BytesGalore/RIOT,OlegHahm/RIOT,kYc0o/RIOT,A-Paul/RIOT,RIOT-OS/RIOT,kaspar030/RIOT,authmillenon/RIOT,RIOT-OS/RIOT,authmillenon/RIOT,A-Paul/RIOT,jasonatran/RIOT,mfrey/RIOT,miri64/RIOT,OTAkeys/RIOT,aeneby/RIOT,kYc0o/RIOT,miri64/RIOT,authmillenon/RIOT,A-Paul/RIOT,mtausig/RIOT,josephnoir/RIOT,RIOT-OS/RIOT,mfrey/RIOT,kYc0o/RIOT,kYc0o/RIOT,lazytech-org/RIOT,kaspar030/RIOT,josephnoir/RIOT,cladmi/RIOT,aeneby/RIOT,toonst/RIOT,kaspar030/RIOT,yogo1212/RIOT,kYc0o/RIOT,mfrey/RIOT,BytesGalore/RIOT,miri64/RIOT,aeneby/RIOT,mtausig/RIOT,OTAkeys/RIOT,rfuentess/RIOT,josephnoir/RIOT,mtausig/RIOT,basilfx/RIOT,mfrey/RIOT,lazytech-org/RIOT,mtausig/RIOT,smlng/RIOT,jasonatran/RIOT