Metaknight: Remove CONFIG_SYSTEM_UNLOCKED
Metaknight: Remove CONFIG_SYSTEM_UNLOCKED

Progressed enough in development that we no longer need to
force an unlocked state on the EC.

BRANCH=dedede
BUG=b:179635951
TEST=make BOARD=metaknight
Signed-off-by: 3408ceec56c33f5f3e599c74de364b5b60768bb8@quanta.corp-partner.google.com
Change-Id: I4a0ba1a966f84b7b126c6553f6938d209565a7d1
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2706662
Reviewed-by: Henry Sun <26cd8a0b26a8449e909dff5211a18ba277320ec2@google.com>
Reviewed-by: Diana Z <cb2016afc7183e5356c690dc63b4ba817470501a@chromium.org>
Reviewed-by: Aseda Aboagye <12c9b286316a940fd31c24070da5ab64cdd4d0e7@chromium.org>

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