i2c/max6875: Really prevent 24RF08 corruption

i2c-core takes care of the possible corruption of 24RF08 chips for
quite some times, so device devices no longer need to do it. And they
really should not, as applying the prevention twice voids it.

I thought that I had fixed all drivers long ago but apparently I had
missed that one.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Ben Gardner <bgardner@wabtec.com>