KVM: Change is_mmio_pfn to kvm_is_mmio_pfn, and make it common for all archs

Add a kvm_ prefix to avoid polluting kernel's name space.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 10c1146..b3b7598 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -288,6 +288,8 @@
 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu);
 void kvm_vcpu_kick(struct kvm_vcpu *vcpu);
 
+int kvm_is_mmio_pfn(pfn_t pfn);
+
 struct kvm_irq_ack_notifier {
 	struct hlist_node link;
 	unsigned gsi;