Resolve a couple of doxygen warnings.

This resolves a couple of doxygen warnings.  First, the group needed a
name.  Second, all of the functions in the file were added to the group
but doxygen complained about the lack of an end to the grouping.

Signed-off-by: Russell Bryant <russell@russellbryant.net>
Reviewed-by: Steven Dake <sdake@redhat.com>

lib/confdb.c

@@ -119,7 +119,7 @@ static struct iter_context *find_iter_context(struct list_head *list, hdb_handle
 }
 
 /**
- * @defgroup confdb_corosync
+ * @defgroup confdb_corosync confdb
  * @ingroup corosync
  *
  * @{
@@ -1812,3 +1812,7 @@ error_exit:
 
 	return (error);
 }
+
+/**
+ * @}
+ */