tests: Add array bounds check Ensure that mock_keypresses_count is in bounds before accessing the mock_keyflags array. BUG=none TEST=make clean && make runtests BRANCH=none Change-Id: Ifa8fce5438f2e2547c9e316038466244eee7bfa9 Signed-off-by: Jacob Garber <[email protected]> Found-by: Coverity CID 198899 Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/1752048 Reviewed-by: Joel Kitching <[email protected]>