efi_loader: use named constant for efi_dp_from_mem()

When calling efi_dp_from_mem() use a named constant for the memory type.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/cmd/bootefi.c b/cmd/bootefi.c
index 38679ff..cc0f292 100644
--- a/cmd/bootefi.c
+++ b/cmd/bootefi.c
@@ -386,7 +386,7 @@
 	if (!device_path && !image_path) {
 		printf("WARNING: using memory device/image path, this may confuse some payloads!\n");
 		/* actual addresses filled in after efi_load_pe() */
-		memdp = efi_dp_from_mem(0, 0, 0);
+		memdp = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE, 0, 0);
 		device_path = image_path = memdp;
 		/*
 		 * Grub expects that the device path of the loaded image is