Update zsh completion for 'docker service {create,update} {--endpoint-mode,--mode}'

Signed-off-by: Steve Durrheimer <s.durrheimer@gmail.com>

contrib/completion/zsh/_docker

@@ -1066,12 +1066,11 @@ __docker_service_subcommand() {
     opts_help=("(: -)--help[Print usage]")
     opts_create_update=(
         "($help)*--constraint=[Placement constraints]:constraint: "
-        "($help)--endpoint-mode=[Placement constraints]:mode:(VIP DNSRR)"
+        "($help)--endpoint-mode=[Placement constraints]:mode:(dnsrr vip)"
         "($help)*"{-e=,--env=}"[Set environment variables]:env: "
         "($help)*--label=[Service labels]:label: "
         "($help)--limit-cpu=[Limit CPUs]:value: "
         "($help)--limit-memory=[Limit Memory]:value: "
-        "($help)--mode=[Limit Memory]:mode:(global replicated)"
         "($help)*--mount=[Attach a mount to the service]:mount: "
         "($help)--name=[Service name]:name: "
         "($help)*--network=[Network attachments]:network: "
@@ -1095,6 +1094,7 @@ __docker_service_subcommand() {
             _arguments $(__docker_arguments) \
                 $opts_help \
                 $opts_create_update \
+                "($help)--mode=[Service Mode]:mode:(global replicated)" \
                 "($help -): :__docker_images" \
                 "($help -):command: _command_names -e" \
                 "($help -)*::arguments: _normal" && ret=0