interop_dxva2: fix flickering effect

not sure if the present call is mandatory after the IDirect3DDevice9Ex_StretchRect, as I only observed the behavior with IDXVAHD_VideoProcessor_VideoProcessBltHD

fun behavior: if voluntary fill the reserved field of the DXVAHD_STREAM_STATE_INPUT_COLOR_SPACE_DATA with ones, colors gets washed out, but it wasn't flickering