The wrong mask is used, which causes some fan speed control modes
(pwmX_enable) to be incorrectly reported, and some modes to be
impossible to set.

[JD: add subject and description.]
Signed-off-by: Brian Carnes <bmcarnes@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jean Delvare <khali@linux-fr.org>