KVM: x86: fix compilation

Fix rebase breakage from commit 55dd00a7 ("KVM: x86: add
KVM_HC_CLOCK_PAIRING hypercall", 2017-01-24), courtesy of the
"I could have sworn I had pushed the right branch" department.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/x86.c

@@ -6153,7 +6153,7 @@ static int kvm_pv_clock_pairing(struct kvm_vcpu *vcpu, gpa_t paddr,
 {
 	struct kvm_clock_pairing clock_pairing;
 	struct timespec ts;
-	cycle_t cycle;
+	u64 cycle;
 	int ret;
 
 	if (clock_type != KVM_CLOCK_PAIRING_WALLCLOCK)