pgsql: Fix thinko in previous patch to always update pg_class.reltuples

Fix thinko in previous patch to always update pg_class.reltuples/relpages.

I mis-simplified the test where ANALYZE decided if it could get away
without doing anything: under the new regime, that's never allowed.  Per
bug #6068 from Jeff Janes.  Back-patch to 8.4, just like previous patch.

Branch
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REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/68306da4880401ed9fd3b341e67a5e4cd4b8706f

Modified Files
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src/backend/commands/analyze.c |   17 ++---------------
1 files changed, 2 insertions(+), 15 deletions(-)