bootstd: Adjust the default bootmeth order

The existing distro scripts check extlinux and scripts before EFI. Adjust
the default ordering to do the same, to avoid breaking existing flows.

Add some documentation, mentioning that this order will likely change in
future.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reported-by: Da Xue <da@libre.computer>
diff --git a/test/boot/bootflow.c b/test/boot/bootflow.c
index 8a4e090..1c91a94 100644
--- a/test/boot/bootflow.c
+++ b/test/boot/bootflow.c
@@ -27,7 +27,7 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
-extern U_BOOT_DRIVER(bootmeth_script);
+extern U_BOOT_DRIVER(bootmeth_2script);
 
 static int inject_response(struct unit_test_state *uts)
 {
@@ -525,7 +525,7 @@
 
 	/* Enable the script bootmeth too */
 	ut_assertok(uclass_first_device_err(UCLASS_BOOTSTD, &bootstd));
-	ut_assertok(device_bind(bootstd, DM_DRIVER_REF(bootmeth_script),
+	ut_assertok(device_bind(bootstd, DM_DRIVER_REF(bootmeth_2script),
 				"bootmeth_script", 0, ofnode_null(), &dev));
 
 	/* Change the order to include mmc4 */