KVM: Move cpuid code to new file

The cpuid code has grown; put it into a separate file.

Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 54abb40..a7f3e65 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -38,6 +38,7 @@
 #include "irq.h"
 #include "trace.h"
 #include "x86.h"
+#include "cpuid.h"
 
 #ifndef CONFIG_X86_64
 #define mod_64(x, y) ((x) - (y) * div64_u64(x, y))