enable building non-(amd64,arm*,ppc64*) systems.
- d/patches/SIMDe: enable building non-(amd64,arm*,ppc64*) systems.
- d/control: build-dep on libsimde-dev to support the above patch.
- d/upstream/metadata: update the repository & bug links (the repo was renamed).
- d/control,d/rules: add pytest-xdist to speed up test running.
Tested using a riscv64 porterbox