add arm64 qemu-user-static support

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
fix version

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
update changelog to release version 1.6.0+dfsg-2ubuntu3

Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>