Changed `attribute` argument to be optional.

Changed the `attribute` argument of the resource to be optional vs.
required.

builtin/providers/aws/resource_aws_lb_ssl_negotiation_policy.go

@@ -42,7 +42,7 @@ func resourceAwsLBSSLNegotiationPolicy() *schema.Resource {
 
 			"attribute": &schema.Schema{
 				Type:     schema.TypeSet,
-				Required: true,
+				Optional: true,
 				ForceNew: true,
 				Elem: &schema.Resource{
 					Schema: map[string]*schema.Schema{

website/source/docs/providers/aws/r/lb_ssl_negotiation_policy.html.markdown

@@ -70,11 +70,11 @@ The following arguments are supported:
 * `lb_port` - (Required) The load balancer port to which the policy
   should be applied. This must be an active listener on the load
 balancer.
-* `attribute` - (At least one Required) An SSL Negotiation policy attribute. Each has two properties:
+* `attribute` - (Optional) An SSL Negotiation policy attribute. Each has two properties:
 	* `name` - The name of the attribute
 	* `value` - The value of the attribute
 
-To set your attributes, please see the [AWS Elastic Load Balancer Developer Guide](http://docs.aws.amazon.com/ElasticLoadBalancing/latest/DeveloperGuide/elb-security-policy-table.html) for a listing of the supported SSL protocols, SSL options, and SSL ciphers.
+To set your attributes, please see the [AWS Elastic Load Balancing Developer Guide](http://docs.aws.amazon.com/ElasticLoadBalancing/latest/DeveloperGuide/elb-security-policy-table.html) for a listing of the supported SSL protocols, SSL options, and SSL ciphers.
 
 ## Attributes Reference