Hi Sumeet
As per my study there is no as such functionality exist in SAP business one. but there could be one work around.
First Make a new Item through Fixed Asset Master data and capitalize it by the cost of CWIP Item and Inactive your old Item.
For Example there is an Item A which is in CWIP with cost of Rs. 100. Now You should Make New Item suppose B itemcode with same description like Item A through Fixed Asset master data. and capitalize it through Capitalization screen under Fixed asset module with cost Rs. 100.