pgsql: Don't try to use a unopened relation

Don't try to use a unopened relation

Commit 4c9d0901 mistakenly introduced a call to
TransferPredicateLocksToHeapRelation() on an index relation that had
been closed a few lines above.  Moving up an index_open() call that's
below is enough to fix the problem.

Discovered by me while testing an unrelated patch.

Branch
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REL9_2_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/9eb80f2ca75a205949df7dc86019d99fe076eb87

Modified Files
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src/backend/catalog/index.c |    5 ++---
1 files changed, 2 insertions(+), 3 deletions(-)