Fix #1674045 workaround for bootloader case
The initial implementation here has a problem if we spot the
'successful' screen briefly, then the system reboots normally,
reaches the bootloader and proceeds past it all within 10
seconds; in this case we'll never actually spot the bootloader
and do our stuff. This tweak should continue through the code
block immediately if the bootloader shows up during the ten
seconds, otherwise check again for the 'successful' screen and
reboot.
Signed-off-by: Adam Williamson <awilliam@redhat.com>