driver core: make driver_probe_device() static

It's only used inside drivers/base/dd.c
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Link: https://lore.kernel.org/r/20201123111938.18968-1-jwi@linux.ibm.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/base/base.h

@@ -133,7 +133,6 @@ extern void device_release_driver_internal(struct device *dev,
 					   struct device *parent);
 
 extern void driver_detach(struct device_driver *drv);
-extern int driver_probe_device(struct device_driver *drv, struct device *dev);
 extern void driver_deferred_probe_del(struct device *dev);
 extern void device_set_deferred_probe_reason(const struct device *dev,
 					     struct va_format *vaf);

drivers/base/dd.c

@@ -724,7 +724,7 @@ EXPORT_SYMBOL_GPL(wait_for_device_probe);
  *
  * If the device has a parent, runtime-resume the parent before driver probing.
  */
-int driver_probe_device(struct device_driver *drv, struct device *dev)
+static int driver_probe_device(struct device_driver *drv, struct device *dev)
 {
 	int ret = 0;