Use an option to remove value from git-commit-setup-hook

The patch is flimsy and more often than not it did not work properly.

lisp/icejam-flycheck.el

@@ -54,20 +54,7 @@
         (with-current-buffer target
           (setq flymake--diagnostics-buffer-source source)
           (display-buffer (current-buffer))
-          (revert-buffer)))))
-
-  (el-patch-feature 'git-commit)
-  (with-eval-after-load 'git-commit
-    ;; Reverts the contents of this commit:
-    ;; https://github.com/magit/magit/commit/2366db4b3b792fbd191c1d653014bfc6343b270c
-    (el-patch-defun git-commit-setup-capf ()
-      "Set completion-at-point-functions to use cape completions in
-`magit-commit' screens."
-      (setq-local completion-at-point-functions
-                  (list (cape-capf-super #'cape-dabbrev #'yasnippet-capf)
-                        #'cape-file
-                        #'cape-keyword
-                        #'ispell-completion-at-point)))))
+          (revert-buffer))))))
 
 ;; Use flymake, the built in linter/checker.
 (use-package flymake :ensure nil

lisp/icejam-magit.el

@@ -2,7 +2,9 @@
 ;;; Commentary:
 ;;; Code:
 
-(eval-when-compile (defvar icejam-keys-mode-map))
+(eval-when-compile
+  (defvar icejam-keys-mode-map)
+  (declare-function git-commit-setup-capf 'git-commit))
 
 (use-package magit
   :ensure t
@@ -13,7 +15,10 @@
               ("<f5> b" . magit-blame-addition)
               ("<f5> g" . magit-status))
   (:map magit-blame-mode-map
-        ("<f5> b" . 'magit-blame-quit)))
+        ("<f5> b" . 'magit-blame-quit))
+  :config
+  (setopt git-commit-setup-hook
+          (remove #'git-commit-setup-capf git-commit-setup-hook)))
 
 (provide 'icejam-magit)
 ;;; icejam-magit.el ends here