pgsql: Fix error code for canceling statement due to conflict with reco

Fix error code for canceling statement due to conflict with recovery.
All retryable conflict errors now have an error code that indicates that
a retry is possible, correcting my incomplete fix of 2010/05/12

Tatsuo Ishii and Simon Riggs, input from Robert Haas and Florian Pflug

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=6bfa6b0867c370d72cbaeba18d6d3a5d80eae0e7

Modified Files
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src/backend/storage/ipc/standby.c |    2 +-
1 files changed, 1 insertions(+), 1 deletions(-)