GH-99108: Make vectorized versions of Blake2 available on x86, too (#125244)

Accomplished by updating HACL* vendored code from hacl-star/hacl-star@a6a0949 to hacl-star/hacl-star@315a9e4

Co-authored-by: Victor Stinner <[email protected]>
Co-authored-by: Zachary Ware <[email protected]>

Author: 3 people