emacs-packages: Move shm

Use autogenerated modules from melpa instead

pkgs/applications/editors/emacs-modes/melpa-packages.nix

@@ -151,6 +151,10 @@ env NIXPKGS_ALLOW_BROKEN=1 nix-instantiate --show-trace ../../../../ -A emacsPac
         # upstream issue: missing file header
         stgit = markBroken super.stgit;
 
+        shm = super.shm.overrideAttrs (attrs: {
+          propagatedUserEnvPkgs = [ external.structured-haskell-mode ];
+        });
+
         # upstream issue: missing file header
         tawny-mode = markBroken super.tawny-mode;
 

pkgs/top-level/emacs-packages.nix

@@ -410,9 +410,6 @@ let
     stgit = callPackage ../applications/editors/emacs-modes/stgit { };
 
     structured-haskell-mode = self.shm;
-    shm = (melpaPackages self).shm.overrideAttrs (attrs: {
-      propagatedUserEnvPkgs = [ external.structured-haskell-mode ];
-    });
 
     thingatpt-plus = callPackage ../applications/editors/emacs-modes/thingatpt-plus { };