Fix opencl-mode update and unpin it

elisp-packages.nix

@@ -17,6 +17,7 @@
   eself,
   esuper,
   git,
+  lib,
   makeWrapper,
   stdenvNoCC,
   writeText,
@@ -180,6 +181,15 @@
       ./elisp-patches/helm-taskrunner-version.patch
     ];
   };
+  # Upstream renamed from opencl-mode to opencl-c-mode. melpa2nix requires single-file-package file
+  # names match the package name. So rename the package (not the file, just in case someone loads it
+  # explicitly).
+  opencl-mode = esuper.opencl-mode.overrideAttrs (attrs: {
+    ename = "opencl-c-mode";
+    recipe = writeText "opencl-c-mode-recipe" (
+      lib.replaceStrings ["(opencl-mode"] ["(opencl-c-mode"] (
+        lib.readFile attrs.recipe));
+  });
   # reveal.js is not actually an ELisp package. Doom gets straight.el to install it,
   # then makes org-re-reveal use it as data.
   revealjs = stdenvNoCC.mkDerivation {