Correct for the recent prototype changes.

demos/tunala/cb.c

@@ -17,7 +17,7 @@ static int int_verify_depth = 10;
 
 /* This function is largely borrowed from the one used in OpenSSL's "s_client"
  * and "s_server" utilities. */
-void cb_ssl_info(SSL *s, int where, int ret)
+void cb_ssl_info(const SSL *s, int where, int ret)
 {
 	const char *str1, *str2;
 	int w;

demos/tunala/tunala.h

@@ -143,7 +143,7 @@ void buffer_from_BIO(buffer_t *buf, BIO *bio);
 void buffer_to_BIO(buffer_t *buf, BIO *bio);
 
 /* Callbacks */
-void cb_ssl_info(SSL *s, int where, int ret);
+void cb_ssl_info(const SSL *s, int where, int ret);
 void cb_ssl_info_set_output(FILE *fp); /* Called if output should be sent too */
 int cb_ssl_verify(int ok, X509_STORE_CTX *ctx);
 void cb_ssl_verify_set_output(FILE *fp);