pgpool: Fix health check process to not start.

Fix health check process to not start.

Previously pgpool_main() did not start a health check process if the
backend node is down. This prevented auto_failback from working.
Pgpool reads status from pool_status file when "-D" option is not
present. If the status recorded in the file is "down", pgpool will
not start health check process for the node. Since auto_failback is
invoked from health check process, this means that auto_failback does
not work for the backend node.

Fix is, unconditionally start health check process.

Author: Tatsuo Ishii <ishii(at)postgresql(dot)org>
Reported-by: Meng Feilong
Discussion: https://github.com/pgpool/pgpool2/issues/140
Backpatch-through: v4.3

Branch
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V4_7_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=2218b5e56fe4b0df884d7f522c41109891e165f4

Modified Files
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src/main/pgpool_main.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)