pgsql: Fix old bug in log_autovacuum_min_duration code: it was relying

Log Message:
-----------
Fix old bug in log_autovacuum_min_duration code: it was relying on being able
to access a Relation entry it had just closed.  I happened to be testing with
CLOBBER_CACHE_ALWAYS, which made this a guaranteed core dump (at least on
machines where sprintf %s isn't forgiving of a NULL pointer).  It's probably
quite unlikely that it would fail in the field, but a bug is a bug.  Fix by
moving the relation_close call down past the logging action.

Modified Files:
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    pgsql/src/backend/commands:
        analyze.c (r1.140 -> r1.141)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/analyze.c?r1=1.140&r2=1.141)