Update for new libmegapixels_find_config signature

src/main.c

@@ -1448,7 +1448,7 @@ main(int argc, char *argv[])
 #endif
         char configfile[PATH_MAX];
         libmegapixels_init(&state.configuration);
-        if (libmegapixels_find_config(configfile)) {
+        if (libmegapixels_find_config(PATH_MAX, configfile)) {
                 if (!libmegapixels_load_file(state.configuration, configfile)) {
                         fprintf(stderr, "Could not load config\n");
                         return 1;