hdf5_ep

[svn-r8969] Purpose:
    Bug fix.

Description:
    Address two problems:
        - The computation of the scanline in the szip filter was being
            performed in the "can apply" callback routine instead of the
            "set local" routine.
        - The routine which allocated all the chunks for an entire dataset
            (which is invoked when the allocation time is early or late,
            rather than incremental) wasn't recording a failed filter in
            the information for the chunk, causing the library to believe
            that the chunk had the filter applied when it really hadn't.

Solution:
    - Move the scanline computation to the "set local" callback.

    - Record the filter mask with each chunk created when allocating them.

Platforms tested:
    FreeBSD 4.10 (sleipnir) w/szip
    Too obscure to require h5committest