Add Ipv6Prefixes option support in ec2.Instance (review fixes)

Signed-off-by: vaspahomov <vas2142553@gmail.com>

apis/ec2/manualv1alpha1/common.go

@@ -559,7 +559,7 @@ type InstanceNetworkInterfaceSpecification struct {
 	// cannot use this option if you use the Ipv6PrefixCount option.
 	// +optional
 	// +immutable
-	Ipv6Prefixes []Ipv6PrefixSpecificationRequest `json:"ipv6Prefixes"`
+	Ipv6Prefixes []Ipv6PrefixSpecificationRequest `json:"ipv6Prefixes,omitempty"`
 
 	// The ID of the network interface.
 	//

pkg/clients/ec2/instance.go

@@ -505,16 +505,16 @@ func GenerateEC2InstanceIPV6Addresses(addrs []manualv1alpha1.InstanceIPv6Address
 
 // GenerateEC2Ipv6PrefixSpecificationRequest coverts an internal slice of Ipv6PrefixSpecificationRequest into a slice of ec2.Ipv6PrefixSpecificationRequest
 func GenerateEC2Ipv6PrefixSpecificationRequest(prefixes []manualv1alpha1.Ipv6PrefixSpecificationRequest) []types.Ipv6PrefixSpecificationRequest {
-	if prefixes != nil {
-		res := make([]types.Ipv6PrefixSpecificationRequest, len(prefixes))
-		for i, a := range prefixes {
-			res[i] = types.Ipv6PrefixSpecificationRequest{
-				Ipv6Prefix: aws.String(a.Ipv6Prefix),
-			}
+	if len(prefixes) == 0 {
+		return nil
+	}
+	res := make([]types.Ipv6PrefixSpecificationRequest, len(prefixes))
+	for i, a := range prefixes {
+		res[i] = types.Ipv6PrefixSpecificationRequest{
+			Ipv6Prefix: aws.String(a.Ipv6Prefix),
 		}
-		return res
 	}
-	return nil
+	return res
 }
 
 // GenerateInstanceIPV6Addresses coverts a slice of ec2.InstanceIpv6Address into a slice of internal InstanceIPv6Address