base: topology: constify attribute_group structures.

attribute_group are not supposed to change at runtime. All functions
working with attribute_group provided by <linux/sysfs.h> work with
const attribute_group. So mark the non-const structs as const.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/base/topology.c

@@ -105,7 +105,7 @@ static struct attribute *default_attrs[] = {
 	NULL
 };
 
-static struct attribute_group topology_attr_group = {
+static const struct attribute_group topology_attr_group = {
 	.attrs = default_attrs,
 	.name = "topology"
 };