Add the enum value for BindingFlags.DoNotWrapExceptions (#4433)

This was approved here.

https://github.com/dotnet/corefx/issues/22866

This does not implement the feature, it just adds
the member to the enum so that CoreCLR and CoreRT
will agree on the value.

src/System.Private.CoreLib/shared/System/Reflection/BindingFlags.cs

@@ -46,5 +46,6 @@ public enum BindingFlags
 
         // These are a couple of misc attributes used
         IgnoreReturn = 0x01000000,  // This is used in COM Interop
+        DoNotWrapExceptions = 0x02000000, // Disables wrapping exceptions in TargetInvocationException
     }
 }