c++/winrt signature for UInt32 is now uint32_t (#508)

https://ceapex.visualstudio.com/Engineering/_workitems/edit/242502

Author: maopeixia

mdoc/Mono.Documentation/Updater/Formatters/CppFormatters/CppWinRtFullMemberFormatter.cs

@@ -60,7 +60,7 @@ protected override string GetCppType(string t)
                 case "System.Int32": typeToCompare = "int"; break;
                 case "System.Int64": typeToCompare = "long"; break;
                 case "System.UInt16": typeToCompare = "unsigned short"; break;
-                case "System.UInt32": typeToCompare = "unsigned int"; break;
+                case "System.UInt32": typeToCompare = "uint32_t"; break;
                 case "System.UInt64": typeToCompare = "uint64_t"; break;
 
                 case "System.Single": typeToCompare = "float"; break;