pc87360: consolidate fan helper

This patch consolidates the _set_fan_min() helper routine into the 2
line sysfs-callback wrapper that uses it.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>