[otbn] Update checklist to latest template
[otbn] Update checklist to latest template

Rename AREA_CROSS_CHECK to AREA_CHECK in the D2 checklist to match the
latest template.

Signed-off-by: Philipp Wagner <5a4b10454c30419e54a1570be358a516ff84bb63@lowrisc.org>

lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan