Test the state of SSL_in_init() from the info_callback

Check that in a handshake done event SSL_in_init() is 0 (see #4574)
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6019)

test/sslapitest.c

@@ -4269,6 +4269,12 @@ static void sslapi_info_callback(const SSL *s, int where, int ret)
         info_cb_failed = 1;
         return;
     }
+
+    /* Check that, if we've got SSL_CB_HANDSHAKE_DONE we are not in init */
+    if ((where & SSL_CB_HANDSHAKE_DONE) && SSL_in_init((SSL *)s) != 0) {
+        info_cb_failed = 1;
+        return;
+    }
 }
 
 /*