UBUNTU: SAUCE: vt -- allow grub to request automatic vt_handoff

UBUNTU: SAUCE: vt -- allow grub to request automatic vt_handoff

Grub may be able to select a graphics mode and paint a splash screen
for us.  If so it needs to be able to tell us it has done so.  Add
support for detecting a new graphics mode selected bit in the
screen_info passed over at boot.  Use this to automatically enable
vt_handoff mode.

Signed-off-by: Andy Whitcroft <apw@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Leann Ogasawara <leann.ogasawara@canonical.com>