system_server: add hal_lights permission

system_server needs the permissions to open the lights hal in the same

Bug: 34634317
Test: can change brightness on marlin (tested on internal master)
Change-Id: I11fe59b4ab32e13d6dad246f4e6c56951e051181
(cherry picked from commit 0223ca51f9148692a3d5d0d5723f912ae4f376ce)
diff --git a/public/system_server.te b/public/system_server.te
index 66bd370..218b7ae 100644
--- a/public/system_server.te
+++ b/public/system_server.te
@@ -4,6 +4,9 @@
 type system_server, domain, domain_deprecated, mlstrustedsubject;
+# Attributes for passthrough hals
+typeattribute system_server hal_light;
 # For art.
 allow system_server dalvikcache_data_file:dir r_dir_perms;
 allow system_server dalvikcache_data_file:file { r_file_perms execute };