vboot/minidiag: add *log assignment in diag_get_storage_test_log mock

Subsequent code can potentially access the *log variable after
being set by vb2ex_diag_get_storage_test_log.

BUG=none
TEST=make clean && make runtests
BRANCH=none

Signed-off-by: Joel Kitching <kitching@google.com>
Change-Id: I9c8ed20efecbb4eaff8a8fcdf1f467f7df5147a0
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/2917624
Tested-by: Joel Kitching <kitching@chromium.org>
Commit-Queue: Yu-Ping Wu <yupingso@chromium.org>
Reviewed-by: Yu-Ping Wu <yupingso@chromium.org>
1 file changed