This port employs IDF port of OpenSSL for most common features, others
are discouraged or not supported. The port also introduces several stubs
for OpenSSL functions which ASIO needs to get compiled and linked.
Upstream ASIO supports WolfSSL as SSL/TLS stack, as well, which is
another option for SSL support in ASIO on ESP platform.
1. add openssl option at menuconfig
2. remove SSL_ERR to reduce complexity
3. add more functions about debugging and assert
According these, our coders and customers may use and debug the OpenSSL code easily.
1. add empty function to load private key into SSL context
2. add empty function to load certification into SSL context
3. add function to load RSA private key
1. add openssl 'new' and 'free' function
2. add clear unused variate to void warning to appear when compile
3. add internal function 'X509_new' to take the place of 'sk_X509_NAME_new_null' function whitch is openssl stack function
