Change Location parameter from validate set into dynamic lookup

Author: taiwu

src/ResourceManager/AnalysisServices/Commands.AnalysisServices/Commands/NewAzureRmAnalysisServicesServer.cs

@@ -41,10 +41,7 @@ public class NewAnalysisServicesServer : AnalysisServicesCmdletBase
         [Parameter(ValueFromPipelineByPropertyName = true, Position = 2, Mandatory = true,
             HelpMessage = "Azure region where the server should be created.")]
         [ValidateNotNullOrEmpty]
-        [ValidateSet("North Central US", "South Central US", "Central US", "West Europe", "North Europe", "West US",
-            "East US",
-            "East US 2", "Japan East", "Japan West", "Brazil South", "Southeast Asia", "East Asia", "Australia East",
-            "Australia Southeast", IgnoreCase = true)]
+        [LocationCompleter("Microsoft.AnalysisServices")]
         public string Location { get; set; }
 
         [Parameter(ValueFromPipelineByPropertyName = true, Position = 3, Mandatory = true,