This patch adds a new function named "set_fan_status" to complement
its get* counterpart, as well as to avoid code duplication between
"fan_proc_write" and "fan_store".

Also, both functions (get*, set*) are now checking for TOS_FAILURE,
TOS_NOT_SUPPORTED and TOS_SUCCESS (to be on par with the rest of the
HCI/SCI functions), printing an error message, returning -ENODEV and
zero respectively.

The proc and sysfs functions were updated to reflect these changes as
well, returning -EIO for proc, and propagating the error value on the
sysfs functions.
Signed-off-by: Azael Avalos <coproscefalo@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>