anaconda-diskroot: wait before dying on media check fail

If a modesetting driver has been loaded by the time the media
check happens, halting the system (as we currently do immediately
if the check fails) blanks the screen, which is confusing for
the user. This adds a warning message and a 12-hour wait before
the system is eventually halted, so the user can see the media
check failure and (presumably) reboot and fix the medium.

It also tweaks the text of the failure message not to call it a
"CD check", since it's not 1998 any more.

Resolves: rhbz#2246410

Signed-off-by: Adam Williamson <awilliam@redhat.com>

dracut/anaconda-diskroot

@@ -25,11 +25,15 @@ run_checkisomd5() {
  state="inactive"
  fi
  if [ "$rc" = "1" ]; then
- die "CD check failed!"
+ warn "Media check failed! We do not recommend using this medium. System will halt in 12 hours"
+ sleep 43200
+ die "Media check failed!"
  exit 1
  fi
  if [ "$state" = "failed" ]; then
- die "CD check failed!"
+ warn "Media check failed! We do not recommend using this medium. System will halt in 12 hours"
+ sleep 43200
+ die "Media check failed!"
  exit 1
  fi
  [ -x /bin/plymouth ] && /bin/plymouth --show-splash