bootstd: Allow EFI bootmgr to support an invalid bootflow

For most testing we don't want this bootmeth to actually do anything. For
the one test where we do, add a test hook to obtain the correct behaviour.
This will allow us to bind the device always, rather than just doing it
for this test.

Signed-off-by: Simon Glass <sjg@chromium.org>
3 files changed