spi25.c: CID1130000: Unchecked return value in default_spi_write_aai()

Backports upstream `commit 87ace663d`.

BUG=chromium:478356
BRANCH=none
TEST=still builds

Change-Id: I0f23df7d8b86d0c796137e48cbaa9a9ab6ff8d2a
Signed-off-by: Edward O'Callaghan <quasisec@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/flashrom/+/1667511
Reviewed-by: Stefan Reinauer <reinauer@google.com>
1 file changed