pgsql: In the final emptying phase of the new GiST buffering build, set

In the final emptying phase of the new GiST buffering build, set the
queuedForEmptying flag correctly on buffer when adding it to the queue.
Also, don't add buffer to the queue if it's there already. These were
harmless oversights; failing to set the flag just means that a buffer might
get added to the queue twice if more tuples are added to it (although that
can't actually happen at this point because all the upper buffers have
already been emptied), and having the same buffer twice in the emptying
queue is harmless. But better be tidy.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/8caf6132c7498b2b9400a5496a29e48c1c0aa516

Modified Files
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src/backend/access/gist/gistbuild.c | 12 ++++++++----
1 files changed, 8 insertions(+), 4 deletions(-)