Add vector erf/erff and input files to libmvec microbenchmark.
libmvec-erf-inputs:
90% Normal random distribution
range: (-6.0, 6.0)
mean: 0.0
sigma: 1.0
10% uniform random distribution in range (-5.9, 5.9)
libmvec-erff-inputs:
90% Normal random distribution
range: (-4.0f, 4.0f)
mean: 0.0f
sigma: 1.0f
10% uniform random distribution in range (-3.9f, 3.9f)
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>