openscenegraph: fix collada implementation

`opencollada` is not the same as `collada-dom`. OpenSceneGraph requires
`collada-dom` to generate some shared object files required by OpenMW.

Co-authored-by: Marius David <marius@mariusdavid.fr>
Signed-off-by: Fernando Rodrigues <alpha@sigmasquadron.net>

pkgs/by-name/op/openscenegraph/package.nix

@@ -32,7 +32,7 @@
   curlSupport ? true,
   curl,
   colladaSupport ? false,
-  opencollada,
+  collada-dom,
   opencascadeSupport ? false,
   opencascade-occt,
   ffmpegSupport ? false,
@@ -98,7 +98,7 @@ stdenv.mkDerivation rec {
     ++ lib.optional gdalSupport gdal
     ++ lib.optional curlSupport curl
     ++ lib.optionals colladaSupport [
-      opencollada
+      collada-dom
       pcre
     ]
     ++ lib.optional opencascadeSupport opencascade-occt
@@ -115,6 +115,8 @@ stdenv.mkDerivation rec {
     ++ lib.optionals withExamples [ fltk ]
     ++ lib.optional (restSupport || colladaSupport) boost;
 
+  env = lib.optionalAttrs colladaSupport { COLLADA_DIR = collada-dom; };
+
   patches = [
     (fetchpatch {
       name = "opencascade-api-patch";