virsh-nwfilter: Unify list command column alignment

Before:
$ virsh nwfilter-list
UUID                                  Name
----------------------------------------------------------------
651d902c-165c-4bcc-8d73-41319af1e6bc  allow-arp
9ae11362-df6b-407f-8864-3bdf5125bf77  allow-dhcp
53b5a9ed-7d46-480f-a201-6d8a503d6533  allow-dhcp-server

After:
$ virsh nwfilter-list
 UUID                                  Name
------------------------------------------------------------------
 651d902c-165c-4bcc-8d73-41319af1e6bc  allow-arp
 9ae11362-df6b-407f-8864-3bdf5125bf77  allow-dhcp
 53b5a9ed-7d46-480f-a201-6d8a503d6533  allow-dhcp-server

tools/virsh-nwfilter.c

@@ -370,15 +370,15 @@ cmdNWFilterList(vshControl *ctl, const vshCmd *cmd ATTRIBUTE_UNUSED)
     if (!(list = vshNWFilterListCollect(ctl, 0)))
         return false;
 
-    vshPrintExtra(ctl, "%-36s  %-20s \n", _("UUID"), _("Name"));
-    vshPrintExtra(ctl,
-       "----------------------------------------------------------------\n");
+    vshPrintExtra(ctl, " %-36s  %-20s \n", _("UUID"), _("Name"));
+    vshPrintExtra(ctl, "---------------------------------"
+                       "---------------------------------\n");
 
     for (i = 0; i < list->nfilters; i++) {
         virNWFilterPtr nwfilter = list->filters[i];
 
         virNWFilterGetUUIDString(nwfilter, uuid);
-        vshPrint(ctl, "%-36s  %-20s\n",
+        vshPrint(ctl, " %-36s  %-20s\n",
                  uuid,
                  virNWFilterGetName(nwfilter));
     }