fix python-etcd installtion

Change-Id: I2e3bfef9f4d4ed4603f101b0ff319d6b62119882
diff --git a/etcd/server/service.sls b/etcd/server/service.sls
index 8d6a327..3e1fba1 100644
--- a/etcd/server/service.sls
+++ b/etcd/server/service.sls
@@ -41,7 +41,7 @@
 {%- endif %}
 {%- endfor %}
 
-{%- if _support_pkgs|length > 1 %}
+{%- if _support_pkgs|length >= 1 %}
 etcd_support_packages:
   pkg.installed:
     - pkgs: