pgsql: Fix outdated src/test/mb/ tests, and add a GB18030 test.

Fix outdated src/test/mb/ tests, and add a GB18030 test.

The expected-output files for these tests were broken by the recent
addition of a warning for hash indexes. Update them.

Also add a test case for GB18030 encoding, similar to the other ones.
This is a pretty weak test, but it's better than nothing.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/07af523870bcfe930134054febd3a6a114942e5b

Modified Files
--------------
src/test/mb/expected/big5.out | 1 +
src/test/mb/expected/euc_jp.out | 1 +
src/test/mb/expected/euc_kr.out | 1 +
src/test/mb/expected/euc_tw.out | 1 +
src/test/mb/expected/gb18030.out | 87 ++++++++++++++++++++++++++++++++
src/test/mb/expected/mule_internal.out | 2 +
src/test/mb/expected/sjis.out | 1 +
src/test/mb/expected/utf8.out | 1 +
src/test/mb/mbregress.sh | 11 +++-
src/test/mb/sql/gb18030.sql | 19 +++++++
10 files changed, 124 insertions(+), 1 deletion(-)