driver model: constify attribute groups

Let attribute group vectors be declared "const".  We'd
like to let most attribute metadata live in read-only
sections... this is a start.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/net/bluetooth/hci_sysfs.c b/net/bluetooth/hci_sysfs.c
index 95f7a7a..7f939ce 100644
--- a/net/bluetooth/hci_sysfs.c
+++ b/net/bluetooth/hci_sysfs.c
@@ -68,7 +68,7 @@
 	.attrs = bt_link_attrs,
 };
 
-static struct attribute_group *bt_link_groups[] = {
+static const struct attribute_group *bt_link_groups[] = {
 	&bt_link_group,
 	NULL
 };
@@ -392,7 +392,7 @@
 	.attrs = bt_host_attrs,
 };
 
-static struct attribute_group *bt_host_groups[] = {
+static const struct attribute_group *bt_host_groups[] = {
 	&bt_host_group,
 	NULL
 };