x86: enable MAXSMP

Impact: activates new off-stack cpumask code on MAXSMP (non-default) x86 configs

Set MAXSMP to enable CONFIG_CPUMASK_OFFSTACK which moves cpumask's off
the stack (and in structs) when using cpumask_var_t.

Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Ingo Molnar <mingo@elte.hy>

arch/x86/Kconfig

@@ -591,16 +591,17 @@ config IOMMU_HELPER
 
 config MAXSMP
 	bool "Configure Maximum number of SMP Processors and NUMA Nodes"
-	depends on X86_64 && SMP && BROKEN
+	depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
+	select CPUMASK_OFFSTACK
 	default n
 	help
 	  Configure maximum number of CPUS and NUMA Nodes for this architecture.
 	  If unsure, say N.
 
 config NR_CPUS
-	int "Maximum number of CPUs (2-512)" if !MAXSMP
-	range 2 512
 	depends on SMP
+	int "Maximum number of CPUs" if SMP && !MAXSMP
+	range 2 512 if SMP && !MAXSMP
 	default "4096" if MAXSMP
 	default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
 	default "8"