lisp/org.el (org-set-tags): Simplify further

* lisp/org.el (org-set-tags): Use let* for c0 p0 c1 rpl di tc;
Restructure so that no check on c0 is needed; Don't return a useless
tags var from cond; Change and into an equivalent when.

lisp/org.el

@@ -14985,22 +14985,28 @@ When JUST-ALIGN is non-nil, only align tags."
           ((re-search-forward
             (concat "\\([ \t]*" (regexp-quote current) "\\)[ \t]*$")
             (point-at-eol) t)
-           (let (c0 p0 c1 rpl di tc)
-             (if (equal tags "")
-                 (setq rpl "")
-               (goto-char (match-beginning 0))
-               (setq c0 (current-column)
-                     ;; compute offset for the case of org-indent-mode active
-                     di (if (org-bound-and-true-p org-indent-mode)
+           (if (equal tags "")
+               (replace-match "" t t)
+             (goto-char (match-beginning 0))
+             (let* ((c0 (current-column))
+                    ;; compute offset for the case of org-indent-mode active
+                    (di (if (org-bound-and-true-p org-indent-mode)
                             (* (1- org-indent-indentation-per-level) (1- level))
-                          0)
-                     p0 (if (equal (char-before) ?*) (1+ (point)) (point))
-                     tc (+ org-tags-column (if (> org-tags-column 0) (- di) di))
-                     c1 (max (1+ c0) (if (> tc 0) tc (- (- tc) (string-width tags))))
-                     rpl (concat (make-string (max 0 (- c1 c0)) ?\ ) tags)))
-             (replace-match rpl t t)
-             (and (not (featurep 'xemacs)) c0 indent-tabs-mode (tabify p0 (point)))
-             tags))
+                          0))
+                    (p0 (if (equal (char-before) ?*)
+                            (1+ (point))
+                          (point)))
+                    (tc (+ org-tags-column
+                           (if (> org-tags-column 0)
+                               (- di)
+                             di)))
+                    (c1 (max (1+ c0) (if (> tc 0)
+                                         tc
+                                       (- (- tc) (string-width tags)))))
+                    (rpl (concat (make-string (max 0 (- c1 c0)) ?\ ) tags)))
+               (replace-match rpl t t)
+               (when (and (not (featurep 'xemacs)) indent-tabs-mode)
+                 (tabify p0 (point))))))
           (t (error "Tags alignment failed")))
         (org-move-to-column col)
         (unless just-align