drivers: base: transport_class: fix possible memory leak

Current some drivers(like iscsi) call transport_register_device()
failed, they don't call transport_destroy_device() to release the
memory allocated in transport_setup_device(), because they don't
know what was done, it should be internal thing to release the
resource in register function. So fix this leak by calling destroy
function inside register function.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Yang Yingliang <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

include/linux/transport_class.h

···
 static inline int
 transport_register_device(struct device *dev)
 {
+	int ret;
+
 	transport_setup_device(dev);
-	return transport_add_device(dev);
+	ret = transport_add_device(dev);
+	if (ret)
+		transport_destroy_device(dev);
+
+	return ret;
 }
 
 static inline void