toshiba_acpi: Support additional hotkey scancodes

These scancodes are used by many of the models now supported with
the addition of TOS1900 device support.

Signed-off-by: Azael Avalos <coproscefalo@gmail.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>