pgsql: Initialize pad bytes in GinFormTuple().

Initialize pad bytes in GinFormTuple().

Every other core buffer page consumer initializes the bytes it furnishes
to PageAddItem().  For consistency, do the same here.  No back-patch;
regardless, we couldn't count on the fix so long as binary upgrade can
carry forward affected index builds.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/1d96bb96024c51f5a445f85ec45ce2e9bbd08c56

Modified Files
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src/backend/access/gin/ginentrypage.c |    6 ++++++
1 file changed, 6 insertions(+)