KVM: arm/arm64: vgic-v3: Fix off-by-one LR access

When iterating over the used LRs, be careful not to try to access
an unused LR, or even an unimplemented one if you're unlucky...

Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>

virt/kvm/arm/hyp/vgic-v3-sr.c

@@ -143,7 +143,7 @@ void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu)
 		val = read_gicreg(ICH_VTR_EL2);
 		nr_pri_bits = vtr_to_nr_pri_bits(val);
 
-		for (i = 0; i <= used_lrs; i++) {
+		for (i = 0; i < used_lrs; i++) {
 			if (cpu_if->vgic_elrsr & (1 << i))
 				cpu_if->vgic_lr[i] &= ~ICH_LR_STATE;
 			else