grn_io_seg_map_: fix a resource leak (#1264)
grn_io_seg_map_: fix a resource leak (#1264)

If DO_MAP for newly created file is failed, the opened fileinfo for the
newly created file is not closed. Because unlink does not release file
descriptor/handle.

The file descriptor/handle isn't released until Groonga process is restarted.
komainu8/groonga,komainu8/groonga,kenhys/groonga,komainu8/groonga,kenhys/groonga,groonga/groonga,groonga/groonga,groonga/groonga,kenhys/groonga,kenhys/groonga,kenhys/groonga,groonga/groonga,komainu8/groonga,groonga/groonga,groonga/groonga,groonga/groonga,komainu8/groonga,komainu8/groonga,kenhys/groonga,komainu8/groonga,groonga/groonga,kenhys/groonga,komainu8/groonga,kenhys/groonga