locking/qspinlock: Move __ARCH_SPIN_LOCK_UNLOCKED to qspinlock_types.h

Move the __ARCH_SPIN_LOCK_UNLOCKED definition from qspinlock.h into
qspinlock_types.h.

The definition of __ARCH_SPIN_LOCK_UNLOCKED comes from the build arch's
include files; but on x86 when CONFIG_QUEUED_SPINLOCKS=y, it just
it's defined in asm-generic/qspinlock.h. In most cases, this doesn't
matter because linux/spinlock.h includes asm/spinlock.h, which for x86
includes asm-generic/qspinlock.h. However, any code that only includes
linux/mutex.h will break, because it only includes asm/spinlock_types.h.

For example, this breaks systemtap, which only includes mutex.h.

Signed-off-by: Dan Streetman <[e-mail]>
Signed-off-by: Peter Zijlstra (Intel) <[e-mail]>
Acked-by: Waiman Long <[e-mail]>
Cc: Andrew Morton <[e-mail]>
Cc: Arnd Bergmann <[e-mail]>
Cc: Dan Streetman <[e-mail]>
Cc: Linus Torvalds <[e-mail]>
Cc: Paul E. McKenney <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Ingo Molnar <[e-mail]>

include/asm-generic/qspinlock.h

···
 #endif
 
 /*
- * Initializier
- */
-#define	__ARCH_SPIN_LOCK_UNLOCKED	{ ATOMIC_INIT(0) }
-
-/*
  * Remapping spinlock architecture specific functions to the corresponding
  * queued spinlock functions.
  */

include/asm-generic/qspinlock_types.h

···
 } arch_spinlock_t;
 
 /*
+ * Initializier
+ */
+#define	__ARCH_SPIN_LOCK_UNLOCKED	{ ATOMIC_INIT(0) }
+
+/*
  * Bitfields in the atomic value:
  *
  * When NR_CPUS < 16K