vboot: Switch key to exit RMA to ctrl+s

Make the key that exits the RMA process ctrl+s instead of esc so that it
is less likely that the user will leave without setting the RMA data.

TEST=emerge-drallion depthcharge chromeos-bootimage
     ctrl+s exits RMA

Signed-off-by: Mathew King <mathewk@chromium.org>
Change-Id: Ia9b4f3492a3569fd93e0ea0cc70a305f42bed955
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/2157896
Reviewed-by: Simon Glass <sjg@chromium.org>
Commit-Queue: Simon Glass <sjg@chromium.org>
2 files changed