Staging: comedi: Use DEFINE_SPINLOCK

SPIN_LOCK_UNLOCKED is deprecated.  The following makes the change suggested
in Documentation/spinlocks.txt

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
declarer name DEFINE_SPINLOCK;
identifier xxx_lock;
@@

- spinlock_t xxx_lock = SPIN_LOCK_UNLOCKED;
+ DEFINE_SPINLOCK(xxx_lock);
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/comedi/rt_pend_tq.c

@@ -25,7 +25,7 @@ volatile static struct rt_pend_tq rt_pend_tq[RT_PEND_TQ_SIZE];
 volatile static struct rt_pend_tq *volatile rt_pend_head = rt_pend_tq,
 	*volatile rt_pend_tail = rt_pend_tq;
 int rt_pend_tq_irq = 0;
-spinlock_t rt_pend_tq_lock = SPIN_LOCK_UNLOCKED;
+DEFINE_SPINLOCK(rt_pend_tq_lock);
 
 // WARNING: following code not checked against race conditions yet.
 #define INC_CIRCULAR_PTR(ptr,begin,size) do {if(++(ptr)>=(begin)+(size)) (ptr)=(begin); } while(0)