Enable find-doc-nits to find undocumented symbols since 1.1.1

A previous commit added the ability to find newly undocumented symbols.
We extend this capability to check anything that was newly added since
1.1.1 which is undocumented. A new option -o is added to find-doc-nits
to amend the behaviour of -v or -e to check symbols that were newly
added since the release of 1.1.1.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/9094)