Minor code clean-up

Thanks to Thorsten for this.

lisp/org.el

@@ -13103,7 +13103,7 @@ Returns the new TODO keyword, or nil if no state change should occur."
 (defvar org-last-inserted-timestamp)
 (defvar org-log-post-message)
 (defvar org-log-note-purpose)
-(defvar org-log-note-how)
+(defvar org-log-note-how nil)
 (defvar org-log-note-extra)
 (defun org-auto-repeat-maybe (done-word)
   "Check if the current headline contains a repeated deadline/schedule.
@@ -13502,7 +13502,6 @@ be removed."
 (defvar org-log-note-purpose nil)
 (defvar org-log-note-state nil)
 (defvar org-log-note-previous-state nil)
-(defvar org-log-note-how nil)
 (defvar org-log-note-extra nil)
 (defvar org-log-note-window-configuration nil)
 (defvar org-log-note-return-to (make-marker))