x86-64: Add vector cbrt/cbrtf to libmvec microbenchmark
Add vector cbrt/cbrtf and input files to libmvec microbenchmark.
libmvec-cbrt-inputs:
90% Normal random distribution
range: (-DBL_MAX, DBL_MAX)
mean: 0.0
sigma: 10.0
10% uniform random distribution in range (-1000.0, 1000.0)
libmvec-cbrtf-inputs:
90% Normal random distribution
range: (-FLT_MAX, FLT_MAX)
mean: 0.0f
sigma: 10.0f
10% uniform random distribution in range (-1000.0f, 1000.0f)