According to the devicetree binding the shutdown and device wake
GPIOs are optional. Since commit 
3e81a4ca51a1 ("Bluetooth: hci_bcm:
Mandate presence of shutdown and device wake GPIO") this driver
won't probe anymore on Raspberry Pi 3 and Zero W (no device wake GPIO
connected). So fix this regression by reverting this commit partially.
Fixes: 3e81a4ca51a1 ("Bluetooth: hci_bcm: Mandate presence of shutdown and device wake GPIO")
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
 
        dev->clk = devm_clk_get(dev->dev, NULL);
 
-       dev->device_wakeup = devm_gpiod_get(dev->dev, "device-wakeup",
-                                           GPIOD_OUT_LOW);
+       dev->device_wakeup = devm_gpiod_get_optional(dev->dev, "device-wakeup",
+                                                    GPIOD_OUT_LOW);
        if (IS_ERR(dev->device_wakeup))
                return PTR_ERR(dev->device_wakeup);
 
-       dev->shutdown = devm_gpiod_get(dev->dev, "shutdown", GPIOD_OUT_LOW);
+       dev->shutdown = devm_gpiod_get_optional(dev->dev, "shutdown",
+                                               GPIOD_OUT_LOW);
        if (IS_ERR(dev->shutdown))
                return PTR_ERR(dev->shutdown);