fix selinux dependencies

Change-Id: I45c932cf18dbc1073a86cbab272d2dda9f15fa41

linux/system/selinux.sls

 {%- if system.enabled %}
 
 include:
-- linux.system.package
+- linux.system.repo
 
 {%- if grains.os_family == 'RedHat' %}
 
   selinux.mode:
   - name: {{ system.get('selinux', 'permissive') }}
   - require:
-    - pkg: linux_packages
+    - pkg: linux_repo_prereq_pkgs
 
 {%- endif %}