Hii Paarthiban,
You can add the extension filed in the make task and as already said, you can extend it to Resource Utilisation Datasource.
I have created a extension field in the make task and extended it to Resource Utilisation datasource and here you can see below i am able to add it to my report.
Thanks & Regards,
Anant Patel
SAP BYD FUNCTIONAL CONSULTANT
Phone: +91-9716100326
Email: anant3113@gmail.com
Skype: anant.3105