Fix util/find-doc-nits to correctly parse function signature typedefs
Fix util/find-doc-nits to correctly parse function signature typedefs

Reviewed-by: Matt Caswell <1fa2ef4755a9226cb9a0a4840bd89b158ac71391@openssl.org>
Reviewed-by: Bernd Edlinger <ac6902843ae77cc0d49b9c8ddec4cbf141db1bb7@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/4499)

openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl