Update gccemacs support

To add support for "update 11", see:
http://akrl.sdf.org/gccemacs.html#org4b11ea1

Also:
+ Move eln files to ~/.emacs.d/.local/cache/eln
+ Disable comp-deferred-compilation by default (now that it is
  enabled-by-default upstream).

core/core-packages.el

@@ -97,9 +97,7 @@ uses a straight or package.el command directly).")
       ;; we don't have to deal with them at all.
       autoload-compute-prefixes nil
       ;; We handle it ourselves
-      straight-fix-org nil
-      ;; HACK Disable native-compilation for some troublesome files
-      comp-deferred-compilation-black-list '("/evil-collection-vterm\\.el$"))
+      straight-fix-org nil)
 
 (with-eval-after-load 'straight
   ;; `let-alist' is built into Emacs 26 and onwards