ectool: Add maintenance fpmode
ectool: Add maintenance fpmode

BRANCH=none
BUG=b:184783529
TEST=make buildall -j
TEST=# deployed to dratini device.
     # lock device
     ectool --name=cros_fp fpmode maintenance
     # check that fp unlock doesn't work

Change-Id: Iefce2e2627e880dd118e6ce6479209643b414c13
Signed-off-by: Craig Hesling <383db090fd8ef907a606ac8a9eccd2962bc489cf@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2856293
Commit-Queue: Ting Shen <c671d3efec3d7e7e285f3788bf0d1ba4c8605b78@chromium.org>
Reviewed-by: Ting Shen <c671d3efec3d7e7e285f3788bf0d1ba4c8605b78@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec