Make ppp domain enforcing.

Change-Id: If6b85fbb2332f7a03b603f2d46bd2f73c778ecf9
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
diff --git a/ppp.te b/ppp.te
index fb8641a..af7062b 100644
--- a/ppp.te
+++ b/ppp.te
@@ -1,6 +1,5 @@
 # Point to Point Protocol daemon
 type ppp, domain;
-permissive_or_unconfined(ppp)
 type ppp_device, dev_type;
 type ppp_exec, exec_type, file_type;
 domain_auto_trans(mtp, ppp_exec, ppp)