OpenSSL: Use SSL_cache_hit() when available

This is going to be required for OpenSSL 1.1.0 which makes the SSL
structure opaque. Older versions starting from OpenSSL 1.0.1 include
this function, so start using it now based on OPENSSL_VERSION_NUMBER.

Signed-off-by: Jouni Malinen <j@w1.fi>

src/crypto/tls_openssl.c

@@ -2902,7 +2902,11 @@ struct wpabuf * tls_connection_decrypt(void *tls_ctx,
 
 int tls_connection_resumed(void *ssl_ctx, struct tls_connection *conn)
 {
+#if OPENSSL_VERSION_NUMBER >= 0x10001000L
+	return conn ? SSL_cache_hit(conn->ssl) : 0;
+#else
 	return conn ? conn->ssl->hit : 0;
+#endif
 }