[master]: Add support for s390x architecture, based on s390.

Signed-off-by: Manoj Srivastava <srivasta@golden-gryphon.com>
[master]: Ass support for s390x, and fix installation of conffiles in /etc/etc/

There was a bug in the dh install configuration file, that moved all
kernel-package conf files to /etc/etc/. This commit fixes that.
(Closes: #751751).

jumped on a s390x porterbox, and created initial support for a s390x
architecture, based mostly on what we did for s390. (Closes: #750604).

Signed-off-by: Manoj Srivastava <srivasta@golden-gryphon.com>