sepolicy - move public clatd to private

Clatd is effectively an internal implementation detail of netd.
It exists as a separate daemon only because this gives us a better
security boundary.  Netd is it's only launcher (via fork/exec) and
killer.

Generated via:
  { echo; cat public/clatd.te; echo; } >> private/clatd.te
  rm -f public/clatd.te

  plus a minor edit to put coredomain after clatd type declaration
  and required changes to move netd's clatd use out of public into private.

Test: build and install on non-aosp test device, atest, check for selinux clat denials
Change-Id: I80f110b75828f3657986e64650ef9e0f9877a07c
diff --git a/private/netd.te b/private/netd.te
index 4c129b7..41473b7 100644
--- a/private/netd.te
+++ b/private/netd.te
@@ -5,8 +5,9 @@
 # Allow netd to spawn dnsmasq in it's own domain
 domain_auto_trans(netd, dnsmasq_exec, dnsmasq)
 
-# Allow netd to start clatd in its own domain
+# Allow netd to start clatd in its own domain and kill it
 domain_auto_trans(netd, clatd_exec, clatd)
+allow netd clatd:process signal;
 
 # give netd permission to setup iptables rule with xt_bpf, attach program to cgroup, and read/write
 # the map created by bpfloader