opts: Corrected TLS protocols list to include POP3S rather than POP3

docs/libcurl/opts/CURLOPT_CAINFO.3

docs/libcurl/opts/CURLOPT_CAPATH.3

docs/libcurl/opts/CURLOPT_EGDSOCKET.3

docs/libcurl/opts/CURLOPT_KEYPASSWD.3

docs/libcurl/opts/CURLOPT_PINNEDPUBLICKEY.3

docs/libcurl/opts/CURLOPT_SSLCERT.3

docs/libcurl/opts/CURLOPT_SSLCERTTYPE.3

docs/libcurl/opts/CURLOPT_SSLENGINE.3

docs/libcurl/opts/CURLOPT_SSLENGINE_DEFAULT.3

docs/libcurl/opts/CURLOPT_SSLKEY.3

docs/libcurl/opts/CURLOPT_SSLKEYTYPE.3

docs/libcurl/opts/CURLOPT_SSLVERSION.3

docs/libcurl/opts/CURLOPT_SSL_CIPHER_LIST.3

docs/libcurl/opts/CURLOPT_SSL_CTX_DATA.3

docs/libcurl/opts/CURLOPT_SSL_CTX_FUNCTION.3

docs/libcurl/opts/CURLOPT_SSL_FALSESTART.3

docs/libcurl/opts/CURLOPT_SSL_VERIFYHOST.3

docs/libcurl/opts/CURLOPT_SSL_VERIFYPEER.3

docs/libcurl/opts/CURLOPT_SSL_VERIFYSTATUS.3