locking/rwsem: Fix warnings for CONFIG_RWSEM_GENERIC_SPINLOCK

Optimistic spinning is only used by the xadd variant
of rw-semaphores. Make sure that we use the old version
of the __RWSEM_INITIALIZER macro for systems that rely
on the spinlock one, otherwise warnings can be triggered,
such as the following reported on an arm box:

  ipc/ipcns_notifier.c:22:8: warning: excess elements in struct initializer [enabled by default]
  ipc/ipcns_notifier.c:22:8: warning: (near initialization for 'ipcns_chain.rwsem') [enabled by default]
  ipc/ipcns_notifier.c:22:8: warning: excess elements in struct initializer [enabled by default]
  ipc/ipcns_notifier.c:22:8: warning: (near initialization for 'ipcns_chain.rwsem') [enabled by default]

Signed-off-by: Davidlohr Bueso <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Cc: Tim Chen <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Paul McKenney <[email protected]>
Cc: Michel Lespinasse <[email protected]>
Cc: Peter Hurley <[email protected]>
Cc: Alex Shi <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Andrea Arcangeli <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Jason Low <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Chris Mason <[email protected]>
Cc: Josef Bacik <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

Author: Davidlohr Bueso

include/linux/rwsem.h

@@ -64,7 +64,7 @@ static inline int rwsem_is_locked(struct rw_semaphore *sem)
 # define __RWSEM_DEP_MAP_INIT(lockname)
 #endif
 
-#ifdef CONFIG_SMP
+#if defined(CONFIG_SMP) && !defined(CONFIG_RWSEM_GENERIC_SPINLOCK)
 #define __RWSEM_INITIALIZER(name)			\
 	{ RWSEM_UNLOCKED_VALUE,				\
 	  __RAW_SPIN_LOCK_UNLOCKED(name.wait_lock),	\