pcmcia: add locking to set_mem_map()

Protect the pccard_operations callback "set_mem_map" by a new
mutex ops_mutex. This mutex also protects the following values
in struct pcmcia_socket:

        pccard_mem_map          win[]
        pccard_mem_map          cis_mem
        void __iomem            *cis_virt

Tested-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
diff --git a/include/pcmcia/ss.h b/include/pcmcia/ss.h
index 9ab53d8..e756069 100644
--- a/include/pcmcia/ss.h
+++ b/include/pcmcia/ss.h
@@ -203,6 +203,8 @@
 	unsigned int			thread_events;
 	/* protects socket h/w state */
 	struct mutex			skt_mutex;
+	/* protects PCMCIA state */
+	struct mutex			ops_mutex;
 	/* protects thread_events */
 	spinlock_t			thread_lock;