KVM: Move common KVM Kconfig items to new file virt/kvm/Kconfig

Reduce Kconfig code duplication.

Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 8600a09..939b1cb 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -1,12 +1,8 @@
 #
 # KVM configuration
 #
-config HAVE_KVM
-       bool
 
-config HAVE_KVM_IRQCHIP
-       bool
-       default y
+source "virt/kvm/Kconfig"
 
 menuconfig VIRTUALIZATION
 	bool "Virtualization"
@@ -29,6 +25,7 @@
 	select PREEMPT_NOTIFIERS
 	select MMU_NOTIFIER
 	select ANON_INODES
+	select HAVE_KVM_IRQCHIP
 	---help---
 	  Support hosting fully virtualized guest machines using hardware
 	  virtualization extensions.  You will need a fairly recent