[rhel6-branch & master] three s390x patches

[David Cantrell <dcantrell redhat com>]

1) Start rsyslogd from linuxrc.s390

2) Update example ssh command echo'ed to the console at boot.

3) Add support for /boot on LVM.  Works fine in my tests, but I'm not
   crazy about how I determine the reIPL device, but I do not know of
   a better way to get it.  If /boot is on LVM, we still need to know
   of one specific device for reIPL, which is dumped on the console
   by zipl.  Looking at the zipl code shows it relies on
   /lib/s390-tools/zipl_helper.device-mapper, which is over 700 lines
   of vomit-inducing perl.  This is where I grew tired of navigating
   this pile of s390tools stuff.  I've found a way to get the reIPL
   device, if there is a better way, I am sure I will hear about it.

-- 
David Cantrell <dcantrell redhat com>
Red Hat / Honolulu, HI