KVM: Fix off-by-one in overflow check of KVM_ASSIGN_SET_MSIX_NR

KVM_MAX_MSIX_PER_DEV implies that up to that many MSI-X entries can be
requested. But the kernel so far rejected already the upper limit.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

virt/kvm/assigned-dev.c

@@ -617,7 +617,7 @@ static int kvm_vm_ioctl_set_msix_nr(struct kvm *kvm,
 	if (adev->entries_nr == 0) {
 		adev->entries_nr = entry_nr->entry_nr;
 		if (adev->entries_nr == 0 ||
-		    adev->entries_nr >= KVM_MAX_MSIX_PER_DEV) {
+		    adev->entries_nr > KVM_MAX_MSIX_PER_DEV) {
 			r = -EINVAL;
 			goto msix_nr_out;
 		}