Adjust vpp-selinux-policy postinstall

Only run semodule command on hosts where selinux
is enabled.

Change-Id: I7bcfc758e44bb0f41ec657ad395352ddb92766eb
Signed-off-by: Matthew Smith <mgsmith@netgate.com>
diff --git a/extras/rpm/vpp.spec b/extras/rpm/vpp.spec
index 1793966..a23cc14 100644
--- a/extras/rpm/vpp.spec
+++ b/extras/rpm/vpp.spec
@@ -325,8 +325,8 @@
 
 %post selinux-policy
 %_format MODULES %{_datadir}/selinux/packages/$x.pp
-%{_sbindir}/semodule -n -X 400 -s %{selinuxtype} -i $MODULES
 if %{_sbindir}/selinuxenabled ; then
+    %{_sbindir}/semodule -n -X 400 -s %{selinuxtype} -i $MODULES
     %{_sbindir}/load_policy
     %relabel_files
 fi