KVM: Add KVM_MMIO kconfig item

s390 doesn't have mmio, this will simplify ifdefing it out.
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/ia64/kvm/Kconfig

@@ -26,6 +26,7 @@ config KVM
 	select ANON_INODES
 	select HAVE_KVM_IRQCHIP
 	select KVM_APIC_ARCHITECTURE
+	select KVM_MMIO
 	---help---
 	  Support hosting fully virtualized guest machines using hardware
 	  virtualization extensions.  You will need a fairly recent

arch/powerpc/kvm/Kconfig

@@ -20,6 +20,7 @@ config KVM
 	bool
 	select PREEMPT_NOTIFIERS
 	select ANON_INODES
+	select KVM_MMIO
 
 config KVM_BOOK3S_64_HANDLER
 	bool

arch/x86/kvm/Kconfig

@@ -29,6 +29,7 @@ config KVM
 	select HAVE_KVM_EVENTFD
 	select KVM_APIC_ARCHITECTURE
 	select USER_RETURN_NOTIFIER
+	select KVM_MMIO
 	---help---
 	  Support hosting fully virtualized guest machines using hardware
 	  virtualization extensions.  You will need a fairly recent

virt/kvm/Kconfig

@@ -12,3 +12,6 @@ config HAVE_KVM_EVENTFD
 
 config KVM_APIC_ARCHITECTURE
        bool
+
+config KVM_MMIO
+       bool