r/aws_ami_copy: Add 'throughput' attribute to 'ebs_block_device' block.

Acceptance test output:

$ make testacc TEST=./aws TESTARGS='-run=TestAccAWSAMICopy_'
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./aws -v -count 1 -parallel 20 -run=TestAccAWSAMICopy_ -timeout 120m
=== RUN   TestAccAWSAMICopy_basic
=== PAUSE TestAccAWSAMICopy_basic
=== RUN   TestAccAWSAMICopy_Description
=== PAUSE TestAccAWSAMICopy_Description
=== RUN   TestAccAWSAMICopy_EnaSupport
=== PAUSE TestAccAWSAMICopy_EnaSupport
=== RUN   TestAccAWSAMICopy_tags
=== PAUSE TestAccAWSAMICopy_tags
=== CONT  TestAccAWSAMICopy_basic
=== CONT  TestAccAWSAMICopy_tags
=== CONT  TestAccAWSAMICopy_EnaSupport
=== CONT  TestAccAWSAMICopy_Description
--- PASS: TestAccAWSAMICopy_EnaSupport (385.38s)
--- PASS: TestAccAWSAMICopy_basic (386.46s)
--- PASS: TestAccAWSAMICopy_Description (397.85s)
--- PASS: TestAccAWSAMICopy_tags (411.06s)
PASS
ok  	github.com/terraform-providers/terraform-provider-aws/aws	411.151s

aws/resource_aws_ami_copy.go

@@ -67,6 +67,11 @@ func resourceAwsAmiCopy() *schema.Resource {
 							Computed: true,
 						},
 
+						"throughput": {
+							Type:     schema.TypeInt,
+							Computed: true,
+						},
+
 						"volume_size": {
 							Type:     schema.TypeInt,
 							Computed: true,
@@ -215,17 +220,16 @@ func resourceAwsAmiCopyCreate(d *schema.ResourceData, meta interface{}) error {
 		return err
 	}
 
-	id := *res.ImageId
-	d.SetId(id)
+	d.SetId(aws.StringValue(res.ImageId))
 	d.Set("manage_ebs_snapshots", true)
 
 	if v := d.Get("tags").(map[string]interface{}); len(v) > 0 {
-		if err := keyvaluetags.Ec2CreateTags(client, id, v); err != nil {
+		if err := keyvaluetags.Ec2CreateTags(client, d.Id(), v); err != nil {
 			return fmt.Errorf("error adding tags: %s", err)
 		}
 	}
 
-	_, err = resourceAwsAmiWaitForAvailable(d.Timeout(schema.TimeoutCreate), id, client)
+	_, err = resourceAwsAmiWaitForAvailable(d.Timeout(schema.TimeoutCreate), d.Id(), client)
 	if err != nil {
 		return err
 	}