remove single_address from bootstrap salt-master config

Change-Id: I90cf5cbc26305884ce9bfaf4ac20ae45b9a752f0
diff --git a/bootstrap.sh b/bootstrap.sh
index 2983d50..88efdd0 100755
--- a/bootstrap.sh
+++ b/bootstrap.sh
@@ -319,7 +319,6 @@
 	- cluster.${CLUSTER_NAME}.infra.config
 	parameters:
 	  _param:
-	    single_address: ${MASTER_IP}
 	    salt_master_host: ${MASTER_IP:-$MASTER_HOSTNAME}
 	    salt_master_base_environment: $SALT_ENV
 	    salt_formula_branch: ${SALT_FORMULAS_BRANCH:-master}