emacsPackages.llvm-mode: extract from manual-packages.nix

pkgs/applications/editors/emacs/elisp-packages/llvm-mode/default.nix

@@ -0,0 +1,17 @@
+{ trivialBuild
+, llvmPackages
+}:
+
+trivialBuild {
+  pname = "llvm-mode";
+  inherit (llvmPackages.llvm) src version;
+
+  postUnpack = ''
+    sourceRoot="$sourceRoot/utils/emacs"
+  '';
+
+  meta = {
+    inherit (llvmPackages.llvm.meta) homepage license;
+    description = "Major mode for the LLVM assembler language";
+  };
+}

pkgs/applications/editors/emacs/elisp-packages/manual-packages.nix

@@ -154,20 +154,7 @@
 
   bqn-mode = callPackage ./bqn-mode { };
 
-  llvm-mode = trivialBuild {
-    pname = "llvm-mode";
-    inherit (pkgs.llvmPackages.llvm) src version;
-
-    dontConfigure = true;
-    buildPhase = ''
-      cp utils/emacs/*.el .
-    '';
-
-    meta = {
-      inherit (pkgs.llvmPackages.llvm.meta) homepage license;
-      description = "Major mode for the LLVM assembler language.";
-    };
-  };
+  llvm-mode = callPackage ./llvm-mode { };
 
   ott-mode = callPackage ./ott-mode { };