haskell.compiler.ghcHEAD: bootstrap using GHC 9.10

GHC 9.6 can be used in a pinch, but not to build e.g. a cross compiler.

(cherry picked from commit 4fb0a4a47c)

pkgs/top-level/haskell-packages.nix

@@ -429,13 +429,8 @@ in {
     ghc910 = compiler.ghc9101;
     ghcHEAD = callPackage ../development/compilers/ghc/head.nix {
       bootPkgs =
-        # For GHC 9.6 no armv7l bindists are available.
-        if stdenv.buildPlatform.isAarch32 then
-          bb.packages.ghc963
-        else if stdenv.buildPlatform.isPower64 && stdenv.buildPlatform.isLittleEndian then
-          bb.packages.ghc963
-        else
-          bb.packages.ghc963Binary;
+        # No suitable bindist packaged yet
+        bb.packages.ghc9101;
       inherit (buildPackages.python3Packages) sphinx;
       # Need to use apple's patched xattr until
       # https://github.com/xattr/xattr/issues/44 and