Update M3DWrapper.h

code/AssetLib/M3D/M3DWrapper.h

@@ -47,7 +47,8 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #ifndef AI_M3DWRAPPER_H_INC
 #define AI_M3DWRAPPER_H_INC
 
-#if !(ASSIMP_BUILD_NO_EXPORT || ASSIMP_BUILD_NO_M3D_EXPORTER) || !ASSIMP_BUILD_NO_M3D_IMPORTER
+#ifndef ASSIMP_BUILD_NO_M3D_IMPORTER
+#if !(ASSIMP_BUILD_NO_EXPORT || ASSIMP_BUILD_NO_M3D_EXPORTER)  
 
 #include <memory>
 #include <vector>
@@ -128,5 +129,6 @@ inline m3d_t *M3DWrapper::M3D() const {
 } // namespace Assimp
 
 #endif
+#endif // ASSIMP_BUILD_NO_M3D_IMPORTER
 
 #endif // AI_M3DWRAPPER_H_INC