remove OSStart as indication host is running

The host firmware (at least for IBM) never implemented this boot
progress when starting the OS. Instead, another host firmware team is
utilizing it to indicate an earlier part of the boot.

Therefore this boot progress code should not be treated as if the host
is running.

Signed-off-by: Andrew Geissler <geissonator@yahoo.com>
Change-Id: I453ec41af804db880a99b62105b510464b147efa