toshiba-acpi: remove MAINTAINERS entry

"I'm not much opposed to marking this driver orphaned.  I haven't used
a Toshiba laptop in four years or so, and disagree with the recent
additions of bluetooth and wireless control to the driver.

--John"

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: John Belmonte <john@neggie.net>
Signed-off-by: Len Brown <len.brown@intel.com>