fix meta/salt with missing pillar

Change-Id: I484f7156dc82ca528307857f41018f4048467f78
diff --git a/salt/meta/salt.yml b/salt/meta/salt.yml
index 8795ed0..1a97657 100644
--- a/salt/meta/salt.yml
+++ b/salt/meta/salt.yml
@@ -9,7 +9,7 @@
     - salt: salt.master
 
 minion:
-  {%- if pillar.salt.minion is defined and pillar.salt.minion.ca is defined %}
+  {%- if pillar.get('salt', {}).get('minion', {}).get('ca') %}
   pki:
     {%- from "salt/map.jinja" import minion with context %}
     x509_signing_policies: