refactor: deprecate appendq!, prependq!, & delq! macros

In the interest of slimming down Doom's core (as we near v3), I've
deprecated these macros. They doesn't really need to exist. Sure, the
alternatives aren't as ergonomic or elegant, but they're good enough
that we don't need these trivial wrappers. Their local uses have been
refactored out as well.

modules/completion/company/config.el

@@ -149,7 +149,7 @@
 
   ;; Don't show documentation in echo area, because company-box displays its own
   ;; in a child frame.
-  (delq! 'company-echo-metadata-frontend company-frontends)
+  (cl-callf2 delq 'company-echo-metadata-frontend company-frontends)
 
   (defun +company-box-icons--elisp-fn (candidate)
     (when (derived-mode-p 'emacs-lisp-mode)

modules/completion/ivy/autoload/ivy.el

@@ -351,7 +351,7 @@ If ARG (universal argument), include all files, even hidden or compressed ones."
                   :require-match t
                   :action (lambda (cand)
                             (let ((mark (cdr cand)))
-                              (delq! (marker-buffer mark) buffers)
+                              (cl-callf2 delq (marker-buffer mark) buffers)
                               (mapc #'kill-buffer buffers)
                               (setq buffers nil)
                               (with-current-buffer (switch-to-buffer (marker-buffer mark))