rapidio/tsi721: convert to modular mport driver

This patch adds an option to build device driver for Tsi721 PCIe-to-SRIO
bridge device as a kernel module.

Currently this module cannot be unloaded because the existing RapidIO
subsystem code does not support dynamic removal of local RapidIO
controllers (TODO).

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Andre van Herk <andre.van.herk@Prodrive.nl>
Cc: Micha Nelissen <micha.nelissen@Prodrive.nl>
Cc: Stef van Os <stef.van.os@Prodrive.nl>
Cc: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rapidio/devices/tsi721.c b/drivers/rapidio/devices/tsi721.c
index a8b2c23..ff7cbf2 100644
--- a/drivers/rapidio/devices/tsi721.c
+++ b/drivers/rapidio/devices/tsi721.c
@@ -2515,9 +2515,8 @@
 	return pci_register_driver(&tsi721_driver);
 }
 
-static void __exit tsi721_exit(void)
-{
-	pci_unregister_driver(&tsi721_driver);
-}
-
 device_initcall(tsi721_init);
+
+MODULE_DESCRIPTION("IDT Tsi721 PCIExpress-to-SRIO bridge driver");
+MODULE_AUTHOR("Integrated Device Technology, Inc.");
+MODULE_LICENSE("GPL");