Improve 'define-ibuffer-op' macro (bug#76222)

Improve 'define-ibuffer-op' macro (bug#76222)

* lisp/ibuf-macs.el (define-ibuffer-op):
Change defun to defalias and place it before the macro-local lets.
* lisp/ibuffer.el:
(ibuffer-do-toggle-lock): Remove declare-function.
(ibuffer-do-toggle-read-only): Remove declare-function.
(ibuffer-do-save): Remove declare-function.
(ibuffer-do-delete): Remove declare-function.
(ibuffer-do-toggle-modified): Remove declare-function.
(ibuffer-do-kill-on-deletion-marks): Remove declare-function.

(cherry picked from commit 5d75c6e44da9f27d28ff60d5dee308f2247a1cf5)