Fix some byte-compiler warnings

--- gnuserv-3.12.8/gnuserv-compat.el
+++ gnuserv-3.12.8/gnuserv-compat.el
@@ -100,7 +100,7 @@
 ;; `delete-frame' and `filtered-frame-list' to handle some device
 ;; stuff.
 
-(if (string-match "XEmacs" (emacs-version))
+(if (featurep 'xemacs)
     nil
   
   ;; XEmacs `make-frame' takes an optional device to create the frame
@@ -140,7 +140,7 @@
 ;; part we use devices.el from the Emacs-W3 distribution.  In some
 ;; places the implementation seems wrong, so we "fix" it!
 
-(if (string-match "XEmacs" (emacs-version))
+(if (featurep 'xemacs)
     nil
 
   (defalias 'device-list 'frame-list)
--- gnuserv-3.12.8/gnuserv.el
+++ gnuserv-3.12.8/gnuserv.el
@@ -455,13 +455,14 @@
 		       gnuserv-view-file-function
 		     gnuserv-find-file-function)
 		   path)
-	  (goto-line line)
+	  (goto-char (point-min))
+	  (forward-line (1- line))
 	  ;; Don't memorize the quick and view buffers.
 	  (unless (or quick view)
 	    (cl-pushnew (current-buffer) (gnuclient-buffers client))
 	    (setq gnuserv-minor-mode t)
 	    ;; Add the "Done" button to the menubar, only in this buffer.
-	    (if (and (featurep 'menubar) current-menubar)
+	    (if (and (eval-when-compile (featurep 'menubar)) current-menubar)
 	      (progn (set-buffer-menubar current-menubar)
 	      (add-menu-button nil ["Done" gnuserv-edit]))
 	      ))
@@ -616,12 +617,11 @@
     (when (null (gnuclient-buffers client))
       (gnuserv-kill-client client)))
   ;; Get rid of the buffer.
-  (save-excursion
-    (set-buffer buffer)
+  (with-current-buffer buffer
     (run-hooks 'gnuserv-done-hook)
     (setq gnuserv-minor-mode nil)
     ;; Delete the menu button.
-    (if (and (featurep 'menubar) current-menubar)
+    (if (and (eval-when-compile (featurep 'menubar)) current-menubar)
       (delete-menu-item '("Done")))
     (funcall (if (gnuserv-temp-file-p buffer)
 		 gnuserv-done-temp-file-function
@@ -685,7 +685,6 @@
 ;; This serves to run the hook and reset
 ;; `allow-deletion-of-last-visible-frame'.
 (defun gnuserv-prepare-shutdown ()
-  (setq allow-deletion-of-last-visible-frame nil)
   (run-hooks 'gnuserv-shutdown-hook))
 
 ;; This is a user-callable function, too.
@@ -716,7 +715,6 @@
     (set-process-sentinel gnuserv-process 'gnuserv-sentinel)
     (set-process-filter gnuserv-process 'gnuserv-process-filter)
     (set-process-query-on-exit-flag gnuserv-process nil)
-    (setq allow-deletion-of-last-visible-frame t)
     (run-hooks 'gnuserv-init-hook)))