Function fill_row_fancy_with_2_uv_rows 

fn fill_row_fancy_with_2_uv_rows<const BPP: usize>(
    row_buffer: &mut [u8],
    y_row: &[u8],
    u_row_1: &[u8],
    u_row_2: &[u8],
    v_row_1: &[u8],
    v_row_2: &[u8],
)

Fills a row with the fancy interpolation as detailed