dm: gpio: Add live tree support

Add support for requesting GPIOs with a live device tree.

This involves adjusting the function signature for the legacy function
gpio_request_by_name_nodev(), so fix up all callers.

Signed-off-by: Simon Glass <sjg@chromium.org>
Fixes to stm32f746-disco.c:
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/usb/host/ehci-vf.c b/drivers/usb/host/ehci-vf.c
index e52cd6a..a7f6f21 100644
--- a/drivers/usb/host/ehci-vf.c
+++ b/drivers/usb/host/ehci-vf.c
@@ -252,8 +252,9 @@
 	}
 
 	if (priv->dr_mode == DR_MODE_OTG) {
-		gpio_request_by_name_nodev(dt_blob, node, "fsl,cdet-gpio", 0,
-					   &priv->cdet_gpio, GPIOD_IS_IN);
+		gpio_request_by_name_nodev(offset_to_ofnode(node),
+					   "fsl,cdet-gpio", 0, &priv->cdet_gpio,
+					   GPIOD_IS_IN);
 		if (dm_gpio_is_valid(&priv->cdet_gpio)) {
 			if (dm_gpio_get_value(&priv->cdet_gpio))
 				priv->init_type = USB_INIT_DEVICE;