hwmon: (thmc50) Stop using I2C_CLIENT_MODULE_PARM

The thmc50 driver is the last user of I2C_CLIENT_MODULE_PARM, and I
would like to get rid of that macro.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Krzysztof Helt <krzysztof.h1@wp.pl>