installer: VCA key as env var for LCM

Change-Id: I0c49f673716377694639f5bf9c1319431157fa3d
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/installers/docker/__lcm__.env b/installers/docker/__lcm__.env
index f0baac4..ee19aff 100644
--- a/installers/docker/__lcm__.env
+++ b/installers/docker/__lcm__.env
@@ -1,2 +1,3 @@
 OSMLCM_VCA_HOST=__JUJU_CONTROLLER_IP__
 OSMLCM_VCA_SECRET=__JUJU_PASSWORD__
+OSMLCM_VCA_PUBKEY=__JUJU_PUBKEY__