hwmon: (lm90) Disable interrupt on suspend

I2C accesses are prohibited and will error out after suspending of the
I2C controller, hence we need to ensure that interrupt won't fire on
suspend when it's too late. Disable interrupt across suspend/resume.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>