toshiba_acpi: Remove unnecessary checks and returns in HCI/SCI functions

A previous patch added explicit feature checks for support, *SUCCESS*
and *FAILURE to the HCI/SCI *{get, set} functions.

This patch removes some unnedded checks to the driver HCI/SCI
functions given that the default error return value is now set to
-EIO, there is no need to check for other error values other than
the ones currently checking for.

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