haskell.compiler.ghc963}: fix up for bootstrapping GHC 9.8 on Darwin

After NixOS#307880 was merged, ld64 is 951.9, which is the version shipped with Xcode 15.4. It is new enough to support all of the linker flags used by the upstream bindist.

The only remaining blockers to bootstrapping with the bindist on Darwin is the GHC issue that tries to use `ar -L`, which creates archives that cannot be linked by ld64. Overriding the setting in the bindist suppresses that behavior.

pkgs/development/compilers/ghc/9.6.3-binary.nix

@@ -299,6 +299,12 @@ stdenv.mkDerivation rec {
  isScript "$i" || continue
  sed -i -e '2i export PATH="${lib.makeBinPath runtimeDeps}:$PATH"' "$i"
  done
+ '' + lib.optionalString stdenv.targetPlatform.isDarwin ''
+ # Work around building with binary GHC on Darwin due to GHC’s use of `ar -L` when it
+ # detects `llvm-ar` even though the resulting archives are not supported by ld64.
+ # https://gitlab.haskell.org/ghc/ghc/-/issues/23188
+ # https://github.com/haskell/cabal/issues/8882
+ sed -i -e 's/,("ar supports -L", "YES")/,("ar supports -L", "NO")/' "$out/lib/ghc-${version}/lib/settings"
  '';
 
  # Apparently necessary for the ghc Alpine (musl) bindist: