Fix marshaling of NativeArrayInfo parameters

[pziezio]

Fixes #269 and many other problems with DirectX2D/11/12 etc.

When parameters with NativeArrayInfo are marshaled MarshalAsAttribute is sometimes missing.

https://github.com/microsoft/CsWin32/blob/main/src/Microsoft.Windows.CsWin32/PointerTypeHandleInfo.cs#L32
In this case marshalAs variable corresponds to element type of the array.
When there is no need for setting specific ArraySubType the MarshalAsAttribute is dropped altogether.
It should be set to just MarshalAs(UnmanagedType.LPArray) without specifying ArraySubType.

https://github.com/microsoft/CsWin32/blob/main/src/Microsoft.Windows.CsWin32/PointerTypeHandleInfo.cs#L57
There is exactly the same code in case of marshaling structs as array. Maybe that caused some confusion.
But in that case dropping MarshalAs is correct.

[ghost]

All CLA requirements met.

[AArnott]

Thanks!