selinux: update my email address

Update my email address since epoch.ncsc.mil no longer exists.
MAINTAINERS and CREDITS are already correct.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Paul Moore <paul@paul-moore.com>
diff --git a/security/selinux/ss/mls.c b/security/selinux/ss/mls.c
index e108884..d9dc34f4 100644
--- a/security/selinux/ss/mls.c
+++ b/security/selinux/ss/mls.c
@@ -1,7 +1,7 @@
 /*
  * Implementation of the multi-level security (MLS) policy.
  *
- * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
+ * Author : Stephen Smalley, <sds@tycho.nsa.gov>
  */
 /*
  * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>