usb: phy: Fix NULL pointer exception during usb_get_phy

Upon initialisation (driver probe) a NULL pointer exception
is triggered. This is due to lack of initialisation of
device field in phy structure, which is used by phy
framework in usb_get_phy().

Fix it by initialising the device field.

Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/phy/phy-gpio-vbus-usb.c b/drivers/usb/phy/phy-gpio-vbus-usb.c
index 1d32af2..8443335 100644
--- a/drivers/usb/phy/phy-gpio-vbus-usb.c
+++ b/drivers/usb/phy/phy-gpio-vbus-usb.c
@@ -266,6 +266,7 @@
 	platform_set_drvdata(pdev, gpio_vbus);
 	gpio_vbus->dev = &pdev->dev;
 	gpio_vbus->phy.label = "gpio-vbus";
+	gpio_vbus->phy.dev = gpio_vbus->dev;
 	gpio_vbus->phy.set_power = gpio_vbus_set_power;
 	gpio_vbus->phy.set_suspend = gpio_vbus_set_suspend;
 	gpio_vbus->phy.state = OTG_STATE_UNDEFINED;