android_ab: Add missing semicolon

Found a missing semicolon in code protected by a #if that will never
evaluate to true due to a separate issue. Fixing this issue before
addressing the #if.

Fixes: 3430f24b ("android_ab: Try backup booloader_message")
Signed-off-by: Colin McAllister <colin.mcallister@garmin.com>
Cc: Joshua Watt <JPEWhacker@gmail.com>
Cc: Simon Glass <sjg@chromium.org>
Signed-off-by: Colin McAllister <colinmca242@gmail.com>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>
Reviewed-by: Igor Opaniuk <igor.opaniuk@gmail.com>
Link: https://lore.kernel.org/r/20240312125729.82695-2-colinmca242@gmail.com


Signed-off-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>