Use 'codespell:ignore' where justifiable

Use 'codespell:ignore' where justifiable

There's this one random string where we have the word "Hellow".  It's a
random string, "correct" spelling is really not important, so we tell
codespell to just ignore that line.

There were also two struct field names...

Reviewed-by: Neil Horman <nhorman@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/29463)