pgsql: Fix minor bug in regexp makesearch() function.

Fix minor bug in regexp makesearch() function.

The list-wrangling here was done wrong, allowing the same state to get
put into the list twice.  The following loop then would clone it twice.
The second clone would wind up with no inarcs, so that there was no
observable misbehavior AFAICT, but a useless state in the finished NFA
isn't an especially good thing.

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/669856714222cc27d6ce08b80ed774e854830673

Modified Files
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src/backend/regex/regcomp.c |   19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)