pgsql: Fix the create_index regression test for Danish collation.

Fix the create_index regression test for Danish collation.

In Danish collations, there are letter combinations which sort
higher than 'Z'.  A test for values > 'WA' was picking up rows
where the value started with 'AA', causing the test to fail.

Backpatch to 9.2, where the failing test was added.

Per report from Svenne Krap and analysis by Jeff Janes

Branch
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REL9_3_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/854ebd0f5fb069a6c96e14cff4965350fb5374a6

Modified Files
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src/test/regress/expected/create_index.out |   12 ++++++------
src/test/regress/sql/create_index.sql      |    4 ++--
2 files changed, 8 insertions(+), 8 deletions(-)