pgsql: Fix access to just-closed relcache entry.

Fix access to just-closed relcache entry.

It might be impossible for this to cause a problem in non-debug builds,
since there'd be no opportunity for the relcache entry to get recycled
before the fetch.  It blows up nicely with -DRELCACHE_FORCE_RELEASE plus
valgrind, though.

Evidently introduced by careless refactoring in commit f0e44751d.
Back-patch accordingly.

Discussion: https://postgr.es/m/27543.1528758304@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/bdc643e5e46f84d55d989980e4ff5f8e2da103c6

Modified Files
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src/backend/commands/tablecmds.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)