pgsql: gistendscan() forgot to free so->giststate.

gistendscan() forgot to free so->giststate.

This oversight led to a massive memory leak --- upwards of 10KB per tuple
--- during creation-time verification of an exclusion constraint based on a
GIST index.  In most other scenarios it'd just be a leak of 10KB that would
be recovered at end of query, so not too significant; though perhaps the
leak would be noticeable in a situation where a GIST index was being used
in a nestloop inner indexscan.  In any case, it's a real leak of long
standing, so patch all supported branches.  Per report from Harald Fuchs.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/0a6cc28500b7a8db7a27cbd0d75e18837fb2e367

Modified Files
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src/backend/access/gist/gistscan.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)