multipart, x509-cert, nethsm-sdk-rs: New packages for ITP #1113986
This provides the missing crates needed for nethsm-pkcs11 (ITP #1113986):
The whole chain can be built with CHROOT_MODE=unshare REPACKAGE=1 dev/chain_build.py multipart x509-cert nethsm-sdk-rs .
nethsm-pkcs11 itself will not be part of debcargo-conf, but rather become a standalone source package.
@fg Adding you here since you offered review and sponsoring, thanks again!