rate_ctr: Store the numeric index as part of 'rate_ctr_group'
diff --git a/include/osmocore/rate_ctr.h b/include/osmocore/rate_ctr.h
index c6a1ace..47fd5a3 100644
--- a/include/osmocore/rate_ctr.h
+++ b/include/osmocore/rate_ctr.h
@@ -49,6 +49,7 @@
 	struct llist_head list;
 	/* Pointer to the counter group class */
 	const struct rate_ctr_group_desc *desc;
+	unsigned int idx;
 	/* The name prefix generated from desc->group_prefix_fmt and index */
 	char *name_prefix;
 	/* Actual counter structures below */