sepolicy: Add rules for non-init namespaces

In kernel 4.7, the capability and capability2 classes were split apart
from cap_userns and cap2_userns (see kernel commit
8e4ff6f228e4722cac74db716e308d1da33d744f). Since then, Android cannot be
run in a container with SELinux in enforcing mode.

This change applies the existing capability rules to user namespaces as
well as the root namespace so that Android running in a container
behaves the same on pre- and post-4.7 kernels.

This is essentially:
  1. New global_capability_class_set and global_capability2_class_set
     that match capability+cap_userns and capability2+cap2_userns,
     respectively.
  2. s/self:capability/self:global_capability_class_set/g
  3. s/self:capability2/self:global_capability2_class_set/g
  4. Add cap_userns and cap2_userns to the existing capability_class_set
     so that it covers all capabilities.  This set was used by several
     neverallow and dontaudit rules, and I confirmed that the new
     classes are still appropriate.

Test: diff new policy against old and confirm that all new rules add
      only cap_userns or cap2_userns;
      Boot ARC++ on a device with the 4.12 kernel.
Bug: crbug.com/754831

Change-Id: I4007eb3a2ecd01b062c4c78d9afee71c530df95f
diff --git a/public/hal_wifi_supplicant.te b/public/hal_wifi_supplicant.te
index 10db826..6bf0d32 100644
--- a/public/hal_wifi_supplicant.te
+++ b/public/hal_wifi_supplicant.te
@@ -12,7 +12,7 @@
 r_dir_file(hal_wifi_supplicant, proc_net)
 
 allow hal_wifi_supplicant kernel:system module_request;
-allow hal_wifi_supplicant self:capability { setuid net_admin setgid net_raw };
+allow hal_wifi_supplicant self:global_capability_class_set { setuid net_admin setgid net_raw };
 allow hal_wifi_supplicant cgroup:dir create_dir_perms;
 allow hal_wifi_supplicant self:netlink_route_socket nlmsg_write;
 allow hal_wifi_supplicant self:netlink_socket create_socket_perms_no_ioctl;