Update the BIO_s_connect documentation after the BIO refactoring.
Update the BIO_s_connect documentation after the BIO refactoring.

The BIO was refactored in 417be660e1cd21a2ee085569ff98b0c4249b5416,
but the manual wasn't fully updated to reflect some of the changes.

Reviewed-by: Rich Salz <c04971a99e5a9ee80eaab4b1deb37e845b0bd697@openssl.org>
Reviewed-by: Ben Kaduk <b34e9dc3dd24827b45bb22e8b76cde1bcb413b0e@mit.edu>
(Merged from https://github.com/openssl/openssl/pull/5007)

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