hwmon: (lm90) Add range check to set_update_interval

When writing the update_interval attribute, the parameter value was
not range checked, which could cause an integer overflow and result
in an arbitrary update interval. Fix by limiting the value range to
<0, 100000>.

Reported-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>