Fix for bug #1901664. Giving a validate set for the type

Author: parvezah

src/ServiceManagement/StorSimple/Commands.StorSimple/Cmdlets/GetAzureStorSimpleDevice.cs

@@ -36,6 +36,7 @@ public class GetAzureStorSimpleDevice : StorSimpleCmdletBase
         public string DeviceName { get; set; }
 
         [Parameter(Position = 1, Mandatory = false, HelpMessage = StorSimpleCmdletHelpMessage.DeviceType)]
+        [ValidateSet("Appliance", "VirtualAppliance")]
         [ValidateNotNullOrEmpty]
         public string Type { get; set; }