toshiba_acpi: Change notify funtion to handle more events

Currently the function toshiba_acpi_notify only takes care of hotkeys,
however, the TOSXXXX devices receive more events that can be useful.

This patch changes the function to be able to handle more events,
and in the process, move all hotkey related code residing in it to
a new function called toshiba_acpi_process_hotkeys.

Signed-off-by: Azael Avalos <coproscefalo@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>