[pgpool-committers: 1689] pgpool: Fix a segmentation fault in parallel mode with system_db_hostna

[Yugo Nagata]

Fix a segmentation fault in parallel mode with system_db_hostname is empty

When system_db_hostname is empty, unix domain socket should be used.
However, the directory containing the socket file was't specified in this
case, and the initialization of system DB connection failed. This caused
segmentation fault, when processing a query to system db.

Branch
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V3_2_STABLE

Details
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http://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=3f80177010326664006bc0dc895d175f3a4dc5cd

Modified Files
--------------
doc/pgpool-en.html |    8 +-
doc/pgpool-ja.html |    5 +-
pool_config.c      | 1462 +++++++++++++++++++++++-----------------------------
pool_config.l      |   41 +-
4 files changed, 678 insertions(+), 838 deletions(-)