Bug#854893: Can't qemu-debootstrap s390x: Unknown CPU definition 'any'

[Rebecca N. Palmer]

Package: qemu-user-static
Version: 1:2.8+dfsg-2
Control: notfound -1 1:2.1+dfsg-12+deb8u6
sid-amd64# KEEP_DEBOOTSTRAP_DIR=1 qemu-debootstrap --arch s390x 
--keyring=/usr/share/keyrings/debian-archive-keyring.gpg sid s390x 
http://ftp.de.debian.org/debian/
[...]
I: Running command: chroot s390x /debootstrap/debootstrap --second-stage
Unknown CPU definition 'any'
Unable to find CPU definition

This affects both sid-s390x and jessie-s390x under sid qemu, but not 
under jessie qemu.