Dear Maintainer,

  Add loongarch64 support, thanks!

Thanks, have you successfully tested this? Does it successfully test
packages under qemu?

Is this required? `qemu-system-loongarch64 -machine help` says virt is
the default anyway. We probably shouldn't be forcing particular options
if it isn't required.

(On arm there is no default, and on riscv64 qemu's default machine is
not virtio-based, so they do need this special case)

    smcv

Hi Zhang,

(CC Dandan as loong64 porter)

Without a reply, we can't handle this request. Can you please follow up?

Paul