toshiba_acpi: Fix the enabling of the Special Functions

Some Toshiba laptops with the "Special Functions" feature enabled
fail to properly enable such feature unless a specific value is
used to enable the hotkey events.

This patch adds a new function called "*_enable_special_functions",
that simply makes a call to the HCI_HOTKEY_EVENT call, but this time
we are using a different parameter to make the "Special Functions"
mode work as expected.

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