pcmcia: avoid messages on module (un)loading

printk() statements on module load or unload are frowned upon. Also,
add a few __init or __exit declarations.

Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

drivers/net/wireless/airo_cs.c

@@ -254,12 +254,12 @@ static struct pcmcia_driver airo_driver = {
 	.resume		= airo_resume,
 };
 
-static int airo_cs_init(void)
+static int __init airo_cs_init(void)
 {
 	return pcmcia_register_driver(&airo_driver);
 }
 
-static void airo_cs_cleanup(void)
+static void __exit airo_cs_cleanup(void)
 {
 	pcmcia_unregister_driver(&airo_driver);
 }