pgsql: Reset unused fields in GIN data leaf page footer.

Reset unused fields in GIN data leaf page footer.

The maxoff field is not used in the new, compressed page format. Let's
reset it when converting an old-format page to the new format. The code
won't care either way, but this makes it possible to use the field for
something else in the future.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/d150ff57812ae01a2f78a55f33a46f9b7febf933

Modified Files
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src/backend/access/gin/gindatapage.c |    5 ++++-
src/backend/access/gin/ginxlog.c     |    1 +
2 files changed, 5 insertions(+), 1 deletion(-)