Fixed etcd formula dependency in mcp11-k8s-calico-minimal cluster

Change-Id: If07d1c028f9698a3745154082f6bac8ab61ce36c
diff --git a/classes/cluster/virtual-mcp11-k8s-calico-minimal/.env b/classes/cluster/virtual-mcp11-k8s-calico-minimal/.env
new file mode 100644
index 0000000..ceab58c
--- /dev/null
+++ b/classes/cluster/virtual-mcp11-k8s-calico-minimal/.env
@@ -0,0 +1 @@
+EXTRA_FORMULAS="etcd"