* tls: negotiate until hs is complete in wolfSSL_read/wolfSSL_write
Don't rely on ssl->options.handShakeSate == HANDSHAKE_DONE to check if
negotiation is needed. wolfSSL_Connect() or wolfSSL_Accept() job may not yet be
completed and/or some messages may be waiting in the buffer because of
non-blocking I/O.
* tests: test case for handshake with wolfSSL_read()/wolfSSL_write()
* doc: clarify wolfSSL_write()
* internal.c: rename: need_negotiate -> ssl_in_handshake
c8f3a8f14b