No. Mantle is a propriety marketing gimmick to sell AMD video cards. AMD had to pay Dice $8 million to get on board with AMD otherwise, it would have never been adopted by them.
http://bf4central.com/2013/10/amdamd-paid-ea-5-million-battlefield-4-deal/
As was said, and just to reaffirm, DX12 will render Mantle moot anyways.