Rollup merge of #47826 - gnzlbg:patch-2, r=alexcrichton
Rollup merge of #47826 - gnzlbg:patch-2, r=alexcrichton

Whitelist v7 feature for ARM and AARCH64.

Needed for `v7` features in `coresimd`.

See https://github.com/rust-lang-nursery/stdsimd/blob/b2f7be24d5043a88427f9a5258ca9a51ede6d029/coresimd/src/arm/v7.rs#L40 which used to work but doesn't anymore.

r? alexcrichton

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