parisc: pdc_stable: constify attribute_group structures.

attribute_groups are not supposed to change at runtime. All functions
working with attribute_groups 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: Helge Deller <deller@gmx.de>

drivers/parisc/pdc_stable.c

@@ -954,7 +954,7 @@ static struct attribute *pdcs_subsys_attrs[] = {
 	NULL,
 };
 
-static struct attribute_group pdcs_attr_group = {
+static const struct attribute_group pdcs_attr_group = {
 	.attrs = pdcs_subsys_attrs,
 };