[pgpool-committers: 7547] pgpool: Doc: update "Installation from RPM" section.

[Tatsuo Ishii]

Doc: update "Installation from RPM" section.

It referred to old Pgpool-II 4.1 and PostgreSQL 12. They now refer to
Pgpool-II 4.2 and PostgreSQL 13. Also use dnf command instead of yum
command.

Branch
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V4_2_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=f5a8f2613f7b0294f3babad890ae206b203a8cc5

Modified Files
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doc.ja/src/sgml/installation-rpm.sgml | 12 ++++++------
doc/src/sgml/installation-rpm.sgml    | 14 +++++++-------
2 files changed, 13 insertions(+), 13 deletions(-)