USB: s3c-hsotg: Export usb_gadget_register_driver()

USB gadget controller drivers normally export their driver registration
function, allowing modular builds of the individual gadget drivers so
do so for s3c-hsotg, fixing builds.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/gadget/s3c-hsotg.c b/drivers/usb/gadget/s3c-hsotg.c
index 4b5dbd0..5fc80a1 100644
--- a/drivers/usb/gadget/s3c-hsotg.c
+++ b/drivers/usb/gadget/s3c-hsotg.c
@@ -2582,6 +2582,7 @@
 	hsotg->gadget.dev.driver = NULL;
 	return ret;
 }
+EXPORT_SYMBOL(usb_gadget_register_driver);
 
 int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
 {