libbfd: fix for cross (based on same from @bgamari)

pkgs/development/libraries/libbfd/default.nix

···
 { stdenv
-, fetchurl, autoreconfHook264, bison, binutils-raw
+, fetchurl, fetchpatch, autoreconfHook264, buildPackages, bison, binutils-raw
 , libiberty, zlib
 }:
 
···
 
   patches = binutils-raw.bintools.patches ++ [
     ../../tools/misc/binutils/build-components-separately.patch
+    (fetchpatch {
+      url = "https://raw.githubusercontent.com/mxe/mxe/e1d4c144ee1994f70f86cf7fd8168fe69bd629c6/src/bfd-1-disable-subdir-doc.patch";
+      sha256 = "0pzb3i74d1r7lhjan376h59a7kirw15j7swwm8pz3zy9lkdqkj6q";
+    })
   ];
 
   # We just want to build libbfd
-  postPatch = ''
+  preConfigure = ''
     cd bfd
   '';
 
+  depsBuildBuilds = [ buildPackages.stdenv.cc ];
   nativeBuildInputs = [ autoreconfHook264 bison ];
   buildInputs = [ libiberty zlib ];
 
-  configurePlatforms = [ "build" "host" ];
+  configurePlatforms = [ "build" "host" "target" ];
   configureFlags = [
     "--enable-targets=all" "--enable-64-bit-bfd"
     "--enable-install-libbfd"
     "--enable-shared"
     "--with-system-zlib"
+    "CC_FOR_BUILD=$(CC)"
   ];
+
+  postInstall = stdenv.lib.optionalString (stdenv.hostPlatform != stdenv.targetPlatform) ''
+    # the build system likes to move things into atypical locations
+    mkdir -p $dev
+    mv $out/${stdenv.hostPlatform.config}/${stdenv.targetPlatform.config}/include $dev/include
+    mv $out/${stdenv.hostPlatform.config}/${stdenv.targetPlatform.config}/lib $out/lib
+  '';
 
   enableParallelBuilding = true;