s4-common: Add platform-specific SELinux policies

Change-Id: I708112a4957a88263ebd48282a3994d62301618f
Revert "s4-common: Use permissive SELinux"

This reverts commit a764e49414103e3bce6aa8929031ef53c1ff65dd.

Change-Id: I4f14130083f35a517c14ea50a4ac05f410e6de4b