We've noticed that openafs was not getting upgraded to the PPA version
on one of our opendev.org mirrors. Switch install of packages to
"latest" to make sure it upgrades (reboots to actually apply change
unresolved issue, but at least package is there).
Also, while looking at this, reorder this to install the PPA first,
then ensure we have the kernel headers, then build the openafs kernel
modules, then install. Add a note about having to install/build the
modules first.
Change-Id: I058f5aa52359276a4013c44acfeb980efe4375a1