json-c: Fix crash on Linux64

Missing define led to a server crash that involves json_tokener_parse_ex (called by CLuaArguments::ReadFromJSONString)

Author: Dutchman101

vendor/json-c/config-linux.h

@@ -137,6 +137,9 @@
 /* Define to 1 if you have the `uselocale' function. */
 #define HAVE_USELOCALE
 
+/* Define to 1 if you have the `duplocale' function. */
+#define HAVE_DUPLOCALE
+
 /* Define to 1 if you have the `vasprintf' function. */
 #define HAVE_VASPRINTF