Update godoc of CapacityReservationGroupID of AzureMachineSpec

Author: arkadeepsen

api/v1beta1/azuremachine_types.go

@@ -145,6 +145,10 @@ type AzureMachineSpec struct {
 
 	// CapacityReservationGroupID specifies the capacity reservation group resource id that should be
 	// used for allocating the virtual machine.
+	// The field size should be greater than 0 and the field input must start with '/'.
+	// The input for capacityReservationGroupID must be similar to '/subscriptions/{subscriptionId}/resourceGroups/{resourceGroupName}/providers/Microsoft.Compute/capacityReservationGroups/{capacityReservationGroupName}'.
+	// The keys which are used should be among 'subscriptions', 'providers' and 'resourcegroups' followed by valid ID or names respectively.
+	// It is optional but may not be changed once set.
 	// +optional
 	CapacityReservationGroupID *string `json:"capacityReservationGroupID,omitempty"`
 }