hwmon: (core) Deprecate hwmon_device_register()

Inform the user that hwmon_device_register() is deprecated,
and suggest conversion to the newest API. Also remove
hwmon_device_register() from the kernel API documentation.

Note that hwmon_device_register() is not marked as __deprecated()
since doing so might result in build errors.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
diff --git a/drivers/hwmon/hwmon.c b/drivers/hwmon/hwmon.c
index 112aae6..971c9eb 100644
--- a/drivers/hwmon/hwmon.c
+++ b/drivers/hwmon/hwmon.c
@@ -691,6 +691,9 @@ EXPORT_SYMBOL_GPL(hwmon_device_register_with_info);
  */
 struct device *hwmon_device_register(struct device *dev)
 {
+	dev_warn(dev,
+		 "hwmon_device_register() is deprecated. Please convert the driver to use hwmon_device_register_with_info().\n");
+
 	return hwmon_device_register_with_groups(dev, NULL, NULL, NULL);
 }
 EXPORT_SYMBOL_GPL(hwmon_device_register);