greybus: arche-platform: ensure wake-detect pin is deasserted

During DB3.5 bringup, it was noted that wake_detect signal was not
properly generating SVC edge IRQ.  To ensure signal goes from low
to high correctly, let's bring signal low (regardless of default
pin state).

Testing Done:
- Used for DB3.5/EVT1.5 hardware during bringup
- Regression tested on DB3.1+ES2, DB3.1+ES3
Signed-off-by: Michael Scott <michael.scott@linaro.org>
Reviewed-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Tested-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/arche-platform.c

@@ -211,6 +211,8 @@ static int arche_platform_probe(struct platform_device *pdev)
 				arche_pdata->wake_detect_gpio);
 		goto exit;
 	}
+	/* deassert wake detect */
+	gpio_direction_output(arche_pdata->wake_detect_gpio, 0);
 
 	arche_pdata->dev = &pdev->dev;
 	INIT_DELAYED_WORK(&arche_pdata->delayed_work, svc_delayed_work);