Add vector exp/expf and input files to libmvec microbenchmark.
libmvec-exp-inputs:
90% Normal random distribution
range: (-708.0, 709.0)
mean: 0.0
sigma: 16.0
10% uniform random distribution in range (-500.0, 500.0)
libmvec-expf-inputs:
90% Normal random distribution
range: (-87.0f, 88.0f)
mean: 0.0f
sigma: 8.0f
10% uniform random distribution in range (-50.0f, 50.0f)
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>