Rollup merge of #59556 - RalfJung:stdsimd, r=gnzlbg
Rollup merge of #59556 - RalfJung:stdsimd, r=gnzlbg

update stdsimd

Cc @gnzlbg

graydon/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,graydon/rust,aidancully/rust,aidancully/rust,graydon/rust,aidancully/rust,aidancully/rust