efi_loader: rename struct efi_initrd_dp to efi_lo_dp_prefix

As we now also store device-tree device-paths in load options rename
struct efi_initrd_dp to efi_lo_dp_prefix.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/lib/efi_loader/initrddump.c b/lib/efi_loader/initrddump.c
index 0004b6b..6151190 100644
--- a/lib/efi_loader/initrddump.c
+++ b/lib/efi_loader/initrddump.c
@@ -33,7 +33,7 @@
  * Device path defined by Linux to identify the handle providing the
  * EFI_LOAD_FILE2_PROTOCOL used for loading the initial ramdisk.
  */
-static const struct efi_initrd_dp initrd_dp = {
+static const struct efi_lo_dp_prefix initrd_dp = {
 	.vendor = {
 		{
 		   DEVICE_PATH_TYPE_MEDIA_DEVICE,