Fix memory leaks in ssl_x509_load() and ssl_key_load(), remove unnecessa...

...ry condition in ssl_x509chain_load()

ssl_x509_load() and ssl_key_load() will leak an SSL struct if SSL_CTX_use_certificate_file() or SSL_CTX_use_PrivateKey_file() fail.  It looks like a similar error was previously fixed in ssl_x509chain_load(), but a redundant check on "rv != 1" remained.