Hello  @sthurangi, 

You should be able to use the SmartObject that was generated from your document library in SharePoint to set the status of the document. All you should have to do it create a SmartObject step in your workflow that calls the 'Check In Document,' 'Check In Document By ID,' 'Check Out Document,' or 'Check Out Document By ID' method from this SmartObject to accomplish this.   

Thanks, 
Samuel