doc: correct the SSL_CTX_set_info_callback(3) manual page

The info callback is not prototyped correctly, and the code
example fails to compile because of const-incorrectness.

Reviewed-by: Paul Dale <pauli@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from #22224)

(cherry picked from commit 92986c0)

doc/man3/SSL_CTX_set_info_callback.pod

@@ -12,11 +12,15 @@ SSL_get_info_callback
 
  #include <openssl/ssl.h>
 
- void SSL_CTX_set_info_callback(SSL_CTX *ctx, void (*callback)());
- void (*SSL_CTX_get_info_callback(const SSL_CTX *ctx))();
+ void SSL_CTX_set_info_callback(SSL_CTX *ctx,
+                                void (*callback) (const SSL *ssl, int type, int val));
 
- void SSL_set_info_callback(SSL *ssl, void (*callback)());
- void (*SSL_get_info_callback(const SSL *ssl))();
+ void (*SSL_CTX_get_info_callback(SSL_CTX *ctx)) (const SSL *ssl, int type, int val);
+
+ void SSL_set_info_callback(SSL *ssl,
+                            void (*callback) (const SSL *ssl, int type, int val));
+
+ void (*SSL_get_info_callback(const SSL *ssl)) (const SSL *ssl, int type, int val);
 
 =head1 DESCRIPTION
 
@@ -119,7 +123,7 @@ SSL_get_info_callback() returns the current setting.
 The following example callback function prints state strings, information
 about alerts being handled and error messages to the B<bio_err> BIO.
 
- void apps_ssl_info_callback(SSL *s, int where, int ret)
+ void apps_ssl_info_callback(const SSL *s, int where, int ret)
  {
      const char *str;
      int w = where & ~SSL_ST_MASK;