Change f to dired-find-file.
(define-key dired-mode-map "c" 'dired-change-marks)
(define-key dired-mode-map "d" 'dired-flag-file-deletion)
(define-key dired-mode-map "e" 'dired-find-file)
- (define-key dired-mode-map "f" 'dired-advertised-find-file)
+ (define-key dired-mode-map "f" 'dired-find-file)
+ (define-key dired-mode-map "\C-m" 'dired-advertised-find-file)
(define-key dired-mode-map "g" 'revert-buffer)
(define-key dired-mode-map "h" 'describe-mode)
(define-key dired-mode-map "i" 'dired-maybe-insert-subdir)