ethernet example: Disable WiFi, enable Ethernet in default config

Ref: https://esp32.com/viewtopic.php?f=2&t=1249

diff --git a/examples/ethernet/ethernet/sdkconfig.defaults b/examples/ethernet/ethernet/sdkconfig.defaults
new file mode 100644 (file)
index 0000000..b4f4c3c
--- /dev/null
+++ b/examples/ethernet/ethernet/sdkconfig.defaults
@@ -0,0 +1,2 @@
+# CONFIG_WIFI_ENABLED is not set
+CONFIG_ETHERNET=y