openscenegraph: Fixing compiling on Darwin

The pull request on OpenSceneGraph contains an explanation of why this
is necessary:
openscenegraph/OpenSceneGraph#1360. This fixes
compiling on Darwin, which was broken by the change to have libtiff
compiled with CMake in 8b72443 which
was merged as part of NixOS#366566.

Author: Palmer Cox

pkgs/development/libraries/openscenegraph/default.nix

@@ -137,6 +137,11 @@ stdenv.mkDerivation rec {
       url = "https://gitweb.gentoo.org/repo/gentoo.git/plain/dev-games/openscenegraph/files/openscenegraph-3.6.5-openexr3.patch?id=0f642d8f09b589166f0e0c0fc84df7673990bf3f";
       hash = "sha256-fdNbkg6Vp7DeDBTe5Zso8qJ5v9uPSXHpQ5XlGkvputk=";
     })
+    # Fix compiling with libtiff when libtiff is compiled using CMake
+    (fetchurl {
+      url = "https://github.com/openscenegraph/OpenSceneGraph/commit/9da8d428f6666427c167b951b03edd21708e1f43.patch";
+      hash = "sha256-YGG/DIHU1f6StbeerZoZrNDm348wYB3ydmVIIGTM7fU=";
+    })
   ];
 
   cmakeFlags =