Replace X-allocation functions with their C89 counterparts

The only remaining X-functions used in server are XNF*, the rest is converted to
plain alloc/calloc/realloc/free/strdup.

X* functions are still exported from server and x* macros are still defined in
header file, so both ABI and API are not affected by this change.

Signed-off-by: Mikhail Gusarov <dottedmag@dottedmag.net>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>

config/config.c

@@ -130,7 +130,7 @@ add_option(InputOption **options, const char *key, const char *value)
 
     for (; *options; options = &(*options)->next)
         ;
-    *options = xcalloc(sizeof(**options), 1);
+    *options = calloc(sizeof(**options), 1);
     if (!*options) /* Yeesh. */
         return;
     (*options)->key = xstrdup(key);