pgsql: Fix brin regression test so it actually tests cidr.

Fix brin regression test so it actually tests cidr.

The problem noted in my previous commit was simpler than I thought:
we weren't getting an index plan because the column wasn't indexed.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/1676e4381f48f7bf211f0965ad23abe10a683818

Modified Files
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src/test/regress/expected/brin.out |   30 ++----------------------------
src/test/regress/sql/brin.sql      |    2 ++
2 files changed, 4 insertions(+), 28 deletions(-)