pcmcia: soc_common: add driver-data pointer

Add a driver-data pointer so that low level drivers can add additional
data to the soc_common pcmcia socket structure.
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>

drivers/pcmcia/soc_common.h

@@ -82,6 +82,7 @@ struct soc_pcmcia_socket {
 #endif
 	struct timer_list	poll_timer;
 	struct list_head	node;
+	void *driver_data;
 };
 
 struct skt_dev_info {