compcert: add missing semicolon in all-packages.nix

pkgs/top-level/all-packages.nix

···
 
   cmucl_binary = callPackage ../development/compilers/cmucl/binary.nix { };
 
-  compcert = callPackage ../development/compilers/compcert {}
+  compcert = callPackage ../development/compilers/compcert {};
 
   cryptol1 = lowPrio (callPackage ../development/compilers/cryptol/1.8.x.nix {});
   cryptol2 = haskellPackages.cryptol;