hwmon: (jc42) fix type mismatch

In set_temp_crit_hyst(), make the variable 'val' have the correct
type for strict_strtoul().

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: stable@kernel.org
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>