[pgpool-committers: 7628] pgpool: Fix copyright.

[Tatsuo Ishii]

Fix copyright.

Pgproto was originally written by me and then contributed to PgPool
Global Development Group in 2018.

Branch
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V4_0_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=418c10bd4f9fae06c0371dd7755f546710cef6a2

Modified Files
--------------
src/tools/pgproto/buffer.c         | 3 ++-
src/tools/pgproto/extended_query.c | 1 +
src/tools/pgproto/main.c           | 3 ++-
src/tools/pgproto/read.c           | 3 ++-
src/tools/pgproto/send.c           | 3 ++-
5 files changed, 9 insertions(+), 4 deletions(-)