[chip, testplan] Update chip testplan
[chip, testplan] Update chip testplan

- This commit addresses the comments and updates from the testplan
review meeting held on 5/25/2021.
- The meeting notes are below:
https://docs.google.com/document/d/1OhPP-HjciwKpIh0wWt1xqPqPf0Y0powmmww6xekwMeE/

- Update OTP ctrl and LC ctrl sections of the chip testplan.

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

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