arm64: perf: Constify static attribute_group structs

The only usage of these is to put their addresses in an array of
pointers to const attribute_group structs. Make them const to allow the
compiler to put them in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>

arch/arm64/kernel/perf_event.c

@@ -280,7 +280,7 @@ armv8pmu_event_attr_is_visible(struct kobject *kobj,
 	return 0;
 }
 
-static struct attribute_group armv8_pmuv3_events_attr_group = {
+static const struct attribute_group armv8_pmuv3_events_attr_group = {
 	.name = "events",
 	.attrs = armv8_pmuv3_event_attrs,
 	.is_visible = armv8pmu_event_attr_is_visible,
@@ -300,7 +300,7 @@ static struct attribute *armv8_pmuv3_format_attrs[] = {
 	NULL,
 };
 
-static struct attribute_group armv8_pmuv3_format_attr_group = {
+static const struct attribute_group armv8_pmuv3_format_attr_group = {
 	.name = "format",
 	.attrs = armv8_pmuv3_format_attrs,
 };
@@ -322,7 +322,7 @@ static struct attribute *armv8_pmuv3_caps_attrs[] = {
 	NULL,
 };
 
-static struct attribute_group armv8_pmuv3_caps_attr_group = {
+static const struct attribute_group armv8_pmuv3_caps_attr_group = {
 	.name = "caps",
 	.attrs = armv8_pmuv3_caps_attrs,
 };