virsh: translate net-info help

Reported by kato.tomoyuki@jp.fujitsu.com at
https://bugzilla.redhat.com/show_bug.cgi?id=749564

* tools/virsh.c (info_network_info): Mark string for translation.

tools/virsh.c

@@ -6650,7 +6650,7 @@ cmdNetworkDumpXML(vshControl *ctl, const vshCmd *cmd)
  */
 static const vshCmdInfo info_network_info[] = {
     {"help", N_("network information")},
-    {"desc", "Returns basic information about the network"},
+    {"desc", N_("Returns basic information about the network")},
     {NULL, NULL}
 };