Set camera index in load_camera

src/parse.c

@@ -210,6 +210,7 @@ load_camera(libmegapixels_devconfig *config, config_t *cfg, const char *name)
 	if (config->cameras == NULL) {
 		return -1;
 	}
+	camera->index = config->count;
 	config->cameras[config->count++] = camera;
 
 	config_setting_t *modes = config_setting_lookup(root, "Modes");