efi_loader: efi_net: Add device path cache

In preparation to support mutiple efi net udevices. Add a device path
cache to support device paths from multiple ethernet udevices.
The device paths can be added to the cache before EFI gets initialized and
the protocols get installed.

Signed-off-by: Adriano Cordova <adriano.cordova@canonical.com>
diff --git a/lib/efi_loader/efi_http.c b/lib/efi_loader/efi_http.c
index 8881625..60309ee 100644
--- a/lib/efi_loader/efi_http.c
+++ b/lib/efi_loader/efi_http.c
@@ -188,7 +188,7 @@
 
 	if (!ipv4_node->use_default_address) {
 		efi_net_set_addr((struct efi_ipv4_address *)&ipv4_node->local_address,
-				 (struct efi_ipv4_address *)&ipv4_node->local_subnet, NULL);
+				 (struct efi_ipv4_address *)&ipv4_node->local_subnet, NULL, NULL);
 	}
 
 	http_instance->current_offset = 0;