KVM: x86: check_nested_events is never NULL

Both Intel and AMD now implement it, so there is no need to check if the
callback is implemented.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/x86.c

@@ -7699,7 +7699,7 @@ static int inject_pending_event(struct kvm_vcpu *vcpu)
 	 * from L2 to L1 due to pending L1 events which require exit
 	 * from L2 to L1.
 	 */
-	if (is_guest_mode(vcpu) && kvm_x86_ops.check_nested_events) {
+	if (is_guest_mode(vcpu)) {
 		r = kvm_x86_ops.check_nested_events(vcpu);
 		if (r != 0)
 			return r;
@@ -7761,7 +7761,7 @@ static int inject_pending_event(struct kvm_vcpu *vcpu)
 		 * proposal and current concerns.  Perhaps we should be setting
 		 * KVM_REQ_EVENT only on certain events and not unconditionally?
 		 */
-		if (is_guest_mode(vcpu) && kvm_x86_ops.check_nested_events) {
+		if (is_guest_mode(vcpu)) {
 			r = kvm_x86_ops.check_nested_events(vcpu);
 			if (r != 0)
 				return r;
@@ -8527,7 +8527,7 @@ static inline int vcpu_block(struct kvm *kvm, struct kvm_vcpu *vcpu)
 
 static inline bool kvm_vcpu_running(struct kvm_vcpu *vcpu)
 {
-	if (is_guest_mode(vcpu) && kvm_x86_ops.check_nested_events)
+	if (is_guest_mode(vcpu))
 		kvm_x86_ops.check_nested_events(vcpu);
 
 	return (vcpu->arch.mp_state == KVM_MP_STATE_RUNNABLE &&