fix linker issues.

code/Common/ImporterRegistry.cpp

@@ -5,8 +5,6 @@ Open Asset Import Library (assimp)
 
 Copyright (c) 2006-2020, assimp team
 
-
-
 All rights reserved.
 
 Redistribution and use of this software in source and binary forms,
@@ -200,9 +198,9 @@ corresponding preprocessor flag to selectively disable formats.
 #ifndef ASSIMP_BUILD_NO_M3D_IMPORTER
 #   include "M3D/M3DImporter.h"
 #endif
-#ifndef ASSIMP_BUILD_NO_STEP_IMPORTER
-#   include "Importer/StepFile/StepFileImporter.h"
-#endif
+//#ifndef ASSIMP_BUILD_NO_STEP_IMPORTER
+//#   include "Importer/StepFile/StepFileImporter.h"
+//#endif
 
 namespace Assimp {
 
@@ -361,9 +359,9 @@ void GetImporterInstanceList(std::vector< BaseImporter* >& out)
 #ifndef ASSIMP_BUILD_NO_MMD_IMPORTER
     out.push_back( new MMDImporter() );
 #endif
-#ifndef ASSIMP_BUILD_NO_STEP_IMPORTER
-    out.push_back(new StepFile::StepFileImporter());
-#endif
+//#ifndef ASSIMP_BUILD_NO_STEP_IMPORTER
+//    out.push_back(new StepFile::StepFileImporter());
+//#endif
 }
 
 /** will delete all registered importers. */