Minor bug fix in start-kubemark-master script

test/kubemark/resources/start-kubemark-master.sh

@@ -456,7 +456,7 @@ fi
 	mkdir -p "${main_etcd_mount_point}/srv/kubernetes"
 	ln -s -f "${main_etcd_mount_point}/srv/kubernetes" /etc/srv/kubernetes
 	# Copy the files to the PD only if they don't exist (so we do it only the first time).
-	if [[ "$(ls -A {main_etcd_mount_point}/srv/kubernetes/)" == "" ]]; then
+	if [[ "$(ls -A ${main_etcd_mount_point}/srv/kubernetes/)" == "" ]]; then
 		cp -r "${KUBE_ROOT}"/k8s_auth_data/* "${main_etcd_mount_point}/srv/kubernetes/"
 	fi
 	# Directory for kube-apiserver to store SSH key (if necessary).