greybus: arche-platform: Set direction of wake/detect gpio in poweroff fn

With support of interrupt based mechanism, gpio is not longer set to
output mode, so gpio_set_value won't work. So use
gpio_direction_output() fn in poweroff(), while setting value on
wake/detect line.

Testing Done: Tested on DB3.5 platform.
Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Reviewed-by: Michael Scott <michael.scott@linaro.org>
Tested-by: Michael Scott <michael.scott@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/arche-platform.c

@@ -266,7 +266,7 @@ static void arche_platform_poweroff_seq(struct arche_platform_drvdata *arche_pda
 	/* If in fw_flashing mode, then no need to repeate things again */
 	if (arche_pdata->state != ARCHE_PLATFORM_STATE_FW_FLASHING) {
 		/* Send disconnect/detach event to SVC */
-		gpio_set_value(arche_pdata->wake_detect_gpio, 0);
+		gpio_direction_output(arche_pdata->wake_detect_gpio, 0);
 		usleep_range(100, 200);
 		spin_lock_irqsave(&arche_pdata->lock, flags);
 		arche_pdata->wake_detect_state = WD_STATE_IDLE;