[IA64] hotplug/ia64: SN Hotplug Driver - PREEMPT/pcibus_info fix

This patch fixes an issue with the PROM and a kernel running with
CONFIG_PREEMPT enabled.  When CONFIG_PREEMPT is enabled, the size of a
spinlock_t changes -- resulting in the PROM writing to an incorrect location.
Signed-off-by: NPrarit Bhargava <prarit@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

include/asm-ia64/sn/pcibr_provider.h

@@ -108,10 +108,11 @@ struct pcibus_info {
 	char                    pbi_hub_xid;
 
 	uint64_t                pbi_devreg[8];
-	spinlock_t              pbi_lock;
 
 	uint32_t		pbi_valid_devices;
 	uint32_t		pbi_enabled_devices;
+
+	spinlock_t              pbi_lock;
 };
 
 /*