[doc, checklist] Improve wording of some V2 items
[doc, checklist] Improve wording of some V2 items

Based on feedback from Ensilica, this commit updates the wording of some
V2 checklist items pertaining to coverage of DUT ports.

Signed-off-by: Srikrishna Iyer <2803d640feace36379942447842f26c7747b4dc3@google.com>

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