driver core: Make driver_deferred_probe_timeout a static variable

It is not used outside of its compilation unit, so there's no need to
export this variable.
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Acked-by: John Stultz <jstultz@google.com>
Link: https://lore.kernel.org/r/20221227232152.3094584-1-javierm@redhat.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/base/dd.c

@@ -257,13 +257,11 @@ static int deferred_devs_show(struct seq_file *s, void *data)
 DEFINE_SHOW_ATTRIBUTE(deferred_devs);
 
 #ifdef CONFIG_MODULES
-int driver_deferred_probe_timeout = 10;
+static int driver_deferred_probe_timeout = 10;
 #else
-int driver_deferred_probe_timeout;
+static int driver_deferred_probe_timeout;
 #endif
 
-EXPORT_SYMBOL_GPL(driver_deferred_probe_timeout);
-
 static int __init deferred_probe_timeout_setup(char *str)
 {
 	int timeout;

include/linux/device/driver.h

@@ -240,7 +240,6 @@ driver_find_device_by_acpi_dev(struct device_driver *drv, const void *adev)
 }
 #endif
 
-extern int driver_deferred_probe_timeout;
 void driver_deferred_probe_add(struct device *dev);
 int driver_deferred_probe_check_state(struct device *dev);
 void driver_init(void);