General refactor (use map.el more)

+ map-delete is shorter and faster than assq-delete-all
+ map-put is simpler than the delete-then-set workflow
+ map-merge is great for merging default and user settings

core/autoload/packages.el

@@ -205,7 +205,7 @@ Used by `doom//packages-install'."
     (when (and (not (package-installed-p name))
                (quelpa-setup-p)
                (assq name quelpa-cache))
-      (setq quelpa-cache (assq-delete-all name quelpa-cache))
+      (map-delete quelpa-cache name)
       (quelpa-save-cache)
       (let ((path (expand-file-name (symbol-name name) quelpa-build-dir)))
         (when (file-exists-p path)
@@ -304,7 +304,7 @@ package.el as appropriate."
     (unless (quelpa-setup-p)
       (error "Could not initialize QUELPA"))
     (when (assq name quelpa-cache)
-      (setq quelpa-cache (assq-delete-all name quelpa-cache))
+      (map-delete quelpa-cache name)
       (quelpa-save-cache)
       (setq quelpa-p t))
     (package-delete (cadr (assq name package-alist)) force-p)