do not append addr option with each nfs remount [#130625]

Index: util-linux-ng-2.12r+2.13pre7/mount/nfsmount.c
===================================================================
--- util-linux-ng-2.12r+2.13pre7.orig/mount/nfsmount.c
+++ util-linux-ng-2.12r+2.13pre7/mount/nfsmount.c
@@ -303,8 +303,11 @@ int nfsmount(const char *spec, const cha
 				  "excessively long option argument\n"));
 		goto fail;
 	}
-	sprintf(new_opts, "%s%saddr=%s",
-		old_opts, *old_opts ? "," : "", s);
+	if (*flags & MS_REMOUNT)
+		strcpy(new_opts, old_opts);
+	else
+		sprintf(new_opts, "%s%saddr=%s",
+			old_opts, *old_opts ? "," : "", s);
 	*extra_opts = xstrdup(new_opts);
 
 	/* Set default options.