security: mark LSM hooks as __ro_after_init

Mark all of the registration hooks as __ro_after_init (via the
__lsm_ro_after_init macro).

Signed-off-by: James Morris <james.l.morris@oracle.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Kees Cook <keescook@chromium.org>
diff --git a/security/security.c b/security/security.c
index 905dad2..d6d18a3 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1628,7 +1628,7 @@
 }
 #endif /* CONFIG_AUDIT */
 
-struct security_hook_heads security_hook_heads = {
+struct security_hook_heads security_hook_heads __lsm_ro_after_init = {
 	.binder_set_context_mgr =
 		LIST_HEAD_INIT(security_hook_heads.binder_set_context_mgr),
 	.binder_transaction =