CORD-2247: Write basic static checker for xproto

Change-Id: I63a96972e16fd8dd62d4dec840eede66cbb26368
diff --git a/lib/xos-genx/xosgenx/checkers/model_policy.xchecker b/lib/xos-genx/xosgenx/checkers/model_policy.xchecker
new file mode 100644
index 0000000..abbdd0d
--- /dev/null
+++ b/lib/xos-genx/xosgenx/checkers/model_policy.xchecker
@@ -0,0 +1,5 @@
+{% for m in proto.messages %}
+{% if not m.options.no_policy %}
+{{ xproto_check_policy(m) }}
+{% endif %}
+{% endfor %}