uefi: Enable the UEFI network wrapper driver.

This driver will be used when attempting netboot.

Change-Id: I15bf860aaf186e7682b3f4f74cded679a520bb57
diff --git a/config/uefi/defconfig b/config/uefi/defconfig
index 62ae3ae..c1916b1 100644
--- a/config/uefi/defconfig
+++ b/config/uefi/defconfig
@@ -32,6 +32,7 @@
 CONFIG_DRIVER_DISPLAY_FRAMEBUFFER=y
 CONFIG_DRIVER_FRAMEBUFFER_UEFI=y
 CONFIG_DRIVER_LAYOUT_UEFI=y
+CONFIG_DRIVER_NET_UEFI=y
 CONFIG_DRIVER_POWER_UEFI=y
 CONFIG_DRIVER_STORAGE_FWDB=y
 CONFIG_DRIVER_STORAGE_UEFI_NV=y