x86: make processor type select depend on CONFIG_EMBEDDED

deselecting one of the CPU type CONFIG_CPU_SUP_* config options
can render a kernel unbootable. Make sure this option is only
available if CONFIG_EMBEDDED is enabled.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

arch/x86/Kconfig.cpu

@@ -420,7 +420,6 @@ config X86_DEBUGCTLMSR
 	depends on !(MK6 || MWINCHIPC6 || MWINCHIP2 || MWINCHIP3D || MCYRIXIII || M586MMX || M586TSC || M586 || M486 || M386)
 
 menuconfig PROCESSOR_SELECT
-	default y
 	bool "Supported processor vendors" if EMBEDDED
 	help
 	  This lets you choose what x86 vendor support code your kernel