Satheesh,
Alternately, you can just select a conversion profile that does not check ATP. SAP standard profile SAP999 will do this. This can be set in the product Master PP/DS Tab 'Conversion Rule'. Or, you can default this rule in PP/DS Global Settings configuration.
You will also have to ensure that your ECC config allows creation of a production order without having to pass an ATP check. Make sure this is possible before you do anything in SCM.
Best Regards,
DB49