faft: Ensure blocking sync is called before reboot

Ensure blocking sync is called before all of servo-triggered reset,
whether warm or cold.

Also, add command 'hdparm' to blocking_sync() to make sure that TUR
has to be sent to SSD for checking the status.

BUG=chrome-os-partner:31300
TEST=Ran FAFT

Change-Id: Ic5e4d98e4b0d6246106f6de94a153562793dde71
Signed-off-by: Ryan Lin <ryan.lin@intel.com>
Reviewed-on: https://chromium-review.googlesource.com/218560
Reviewed-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-by: danny chan <dchan@chromium.org>
1 file changed