commit 52bc9802 upstream.

Prevent setting fan_div from stomping on other fans that share the
same I2C register.
Signed-off-by: Gabriele Gorla <gorlik@penguintown.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>