Rollup merge of #135905 - workingjubilee:softly-sanitize-aarch64-floats, r=rcvalle

Enable kernel sanitizers for aarch64-unknown-none-softfloat

We want kernels to be able to use this bare metal target, so let's enable the sanitizers that kernels want to use.

cc ```@rcvalle``` ```@ojeda``` ```@maurer```

Author: matthiaskrgr