sceneconverter: don't sort mesh attributes by the offset.

What a stupid idea, cuz now it's impossible to know which attribute has
which ID, so using --only-attributes is just a total guesswork,
resulting in meshes that have no positions or other nightmare scenarios.

NOT a good idea, past mosra.

By the way, removing the std::sort() stripped 16 kB off the release
binary size (178 kB before, 162 after). Fancy, C++, very fancy.

src/Magnum/SceneTools/sceneconverter.cpp

@@ -23,7 +23,6 @@
     DEALINGS IN THE SOFTWARE.
 */
 
-#include <algorithm>
 #include <set>
 #include <sstream>
 #include <Corrade/Containers/Optional.h>
@@ -651,11 +650,6 @@ used.)")
                         bounds);
                 }
 
-                std::sort(info.attributes.begin(), info.attributes.end(),
-                    [](const MeshAttributeInfo& a, const MeshAttributeInfo& b) {
-                        return a.offset < b.offset;
-                    });
-
                 arrayAppend(meshInfos, std::move(info));
             }
         }