[IA64] panic if topology_init kzalloc fails

There really is no sense trying to continue if the kzalloc of sysfs_cpus[]
fails in ia64 topology_init.  The code calling into here doesn't check
errors very well, and one ends up with a nonobvious boot failure that
wastes peoples time debugging.

See for example the lkml thread at:
  http://lkml.org/lkml/2006/3/2/215

Since the system is totally dead when this kzalloc fails, not having yet
even booted, might as well announce one's death boldly and plainly.
Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/kernel/topology.c

@@ -67,10 +67,8 @@ static int __init topology_init(void)
 #endif
 
 	sysfs_cpus = kzalloc(sizeof(struct ia64_cpu) * NR_CPUS, GFP_KERNEL);
-	if (!sysfs_cpus) {
-		err = -ENOMEM;
-		goto out;
-	}
+	if (!sysfs_cpus)
+		panic("kzalloc in topology_init failed - NR_CPUS too big?");
 
 	for_each_present_cpu(i) {
 		if((err = arch_register_cpu(i)))