merge hashicorp#14003

* Initial check-in

* Add ovmss sku spilt func

* update recoveryservices and add documentation

* update vendor

* go mod vendor

* update test case to remove depricated field

* Remove support for extensions

* Add note to documentation about extension support

* Split Capacity out of sku_name

* Update sku parsing due to spliting out capacity

* Fix comment format

* Add retry logic

* Update error message for create retry

* Added case for unretryable in retry else case

* Update website/docs/r/orchestrated_virtual_machine_scale_set.html.markdown

Co-authored-by: kt <kt@katbyte.me>

* Update website/docs/r/orchestrated_virtual_machine_scale_set.html.markdown

Co-authored-by: kt <kt@katbyte.me>

* Make instances optional and computed

* Update err msg to match main

* Change field name to termination_notification

* Add TODO note for 3.0

Co-authored-by: kt <kt@katbyte.me>

Author: WodansSon

helpers/azure/sku.go

@@ -4,6 +4,9 @@ import (
 	"fmt"
 	"strconv"
 	"strings"
+
+	"github.com/Azure/azure-sdk-for-go/services/compute/mgmt/2021-07-01/compute"
+	"github.com/hashicorp/terraform-provider-azurerm/utils"
 )
 
 func SplitSku(sku string) (string, int32, error) {
@@ -20,3 +23,50 @@ func SplitSku(sku string) (string, int32, error) {
 
 	return skuParts[0], int32(capacity), nil
 }
+
+func ExpandOrchestratedVirtualMachineScaleSetSku(input string, capacity int) (*compute.Sku, error) {
+	skuParts := strings.Split(input, "_")
+
+	if len(skuParts) < 2 || strings.Contains(input, "__") || strings.Contains(input, " ") {
+		return nil, fmt.Errorf("'sku_name'(%q) is not formatted properly.", input)
+	}
+
+	sku := &compute.Sku{
+		Name:     utils.String(input),
+		Capacity: utils.Int64(int64(capacity)),
+		Tier:     utils.String("Standard"),
+	}
+
+	return sku, nil
+}
+
+func FlattenOrchestratedVirtualMachineScaleSetSku(input *compute.Sku) (*string, error) {
+	var skuName string
+	if input != nil && input.Name != nil {
+		if strings.HasPrefix(strings.ToLower(*input.Name), "standard") {
+			skuName = *input.Name
+		} else {
+			skuName = fmt.Sprintf("Standard_%s", *input.Name)
+		}
+
+		return &skuName, nil
+	}
+
+	return nil, fmt.Errorf("Sku struct 'name' is nil")
+}
+
+func ValidateOrchestratedVirtualMachineScaleSetSku(input interface{}, key string) (warnings []string, errors []error) {
+	v, ok := input.(string)
+	if !ok {
+		errors = append(errors, fmt.Errorf("expected %q to be a string", key))
+		return
+	}
+
+	skuParts := strings.Split(v, "_")
+
+	if len(skuParts) < 2 || strings.Contains(v, "__") || strings.Contains(v, " ") {
+		errors = append(errors, fmt.Errorf("%q(%q) is not formatted properly.", key, v))
+	}
+
+	return
+}