Description:
------------
Debian defaults to using -Werror=format-security when hardening the package and 
that results to compile error.

The patch is very simple (and attached).

Expected result:
----------------
File compiles OK.

Actual result:
--------------
/tmp/buildd/php-mysqlnd-ms-1.5.2/mysqlnd_ms-1.5.2/mysqlnd_ms_config_json.c: In 
function 'mysqlnd_ms_config_json_load_configuration':
/tmp/buildd/php-mysqlnd-ms-1.5.2/mysqlnd_ms-1.5.2/mysqlnd_ms_config_json.c:251:5: 
error: format not a string literal and no format arguments [-Werror=format-
security]
     php_error_docref(NULL TSRMLS_CC, E_WARNING, 
MYSQLND_MS_G(config_startup_error));
     ^
cc1: some warnings being treated as errors
make[1]: *** [mysqlnd_ms_config_json.lo] Error 1