Fix typos.

lisp/wdired.el

@@ -32,7 +32,7 @@
 ;; the files in a "dired" buffer? Now you can do this.  All the power
 ;; of Emacs commands are available to renaming files!
 ;;
-;; This package provides a function that makes the filenames of a a
+;; This package provides a function that makes the filenames of a
 ;; dired buffer editable, by changing the buffer mode (which inhibits
 ;; all of the commands of dired mode). Here you can edit the names of
 ;; one or more files and directories, and when you press C-c C-c, the