(DEBUG_INFO_UNAVAILABLE): Value stored in num_debug_info_entries

    (DEBUG_INFO_UNAVAILABLE): Value stored in num_debug_info_entries
        when the .debug_info section could not be loaded/parsed.
        (process_debug_info): Display the length of the compilation unit
        in hex, so that it corresponds with the offsets that will follow.
        Tell the user if the length was 32-bit or 64-bit.
        If a DIE abbreviation could not be found, tell the user the offset
        of the DIE.
        (free_debug_memory): Do not attempt to free any entries in the
        debug_information array if num_debug_info_entries is set to
        DEBUG_INFO_UNAVAILABLE.