powerpc/windfarm: Remove spurrious sysfs_attr_init()

The windfarm core will do it, so this is a duplicate.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

drivers/macintosh/windfarm_smu_controls.c

@@ -172,7 +172,6 @@ static struct smu_fan_control *smu_fan_create(struct device_node *node,
 
 	fct->fan_type = pwm_fan;
 	fct->ctrl.type = pwm_fan ? WF_CONTROL_PWM_FAN : WF_CONTROL_RPM_FAN;
-	sysfs_attr_init(&fct->ctrl.attr.attr);
 
 	/* We use the name & location here the same way we do for SMU sensors,
 	 * see the comment in windfarm_smu_sensors.c. The locations are a bit