At present the normal update (which happens much later) does not work. This
seems to have something to do with the 'no eviction' mode in the CAR, or at
least moving the microcode update after that causes it not to work.
For now, do an update early on so that it definitely works. Also refuse to
continue unless the microcode update check (later in boot) is successful.
Signed-off-by: Simon Glass <sjg@chromium.org>