pcmcia: simplify locking

replace pcmcia_socket->lock and pcmcia_dev_list_lock by using the
per-socket "ops_mutex", as we do neither need different locks
nor a spinlock here.

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

drivers/pcmcia/cs_internal.h

@@ -182,8 +182,6 @@ int pccard_get_tuple_data(struct pcmcia_socket *s, tuple_t *tuple);
 
 #ifdef CONFIG_PCMCIA_IOCTL
 /* ds.c */
-extern spinlock_t pcmcia_dev_list_lock;
-
 extern struct pcmcia_device *pcmcia_get_dev(struct pcmcia_device *p_dev);
 extern void pcmcia_put_dev(struct pcmcia_device *p_dev);