Created by: wangkuiyi

https://github.com/PaddlePaddle/Paddle/blob/81337368d15e6a08e37066bf1be40f24afa48921/paddle/fluid/operators/math/blas_impl.h#L22-L30

It seems that

1. CBlas is declared here, but not defined -- CBlas; instead of CBlas {};.
2. There is no use of CBlas throughout Fluid codebase.

Should we remove it?