[pgpool-committers: 7090] pgpool: Add AC_PROG_CC_C99 in configure.ac file and fix build error int

[Bo Peng]

Add AC_PROG_CC_C99 in configure.ac file and fix build error introduced by commit a8cc1e26cc204a49bea47eea05c711a981c17484.

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=30d10e63ce8ef009257a154b28bf8846b38cf0e6

Modified Files
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configure                          | 121 ++-----------------------------------
configure.ac                       |   9 ++-
src/context/pool_session_context.c |  12 ----
3 files changed, 14 insertions(+), 128 deletions(-)