pgsql: When outputting the session id in log_line_prefix (%c) or in CSV

When outputting the session id in log_line_prefix (%c) or in CSV log
output mode, cause the hex digits after the period to always be at least
four hex digits, with zero-padding.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/22cc3b35f4d614aff83606a443da475215c6dd84

Modified Files
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src/backend/utils/error/elog.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)