pgsql: Improve pg_ctl's message for shutdown after recovery.

Improve pg_ctl's message for shutdown after recovery.

If pg_ctl tries to start the postmaster, but the postmaster shuts down
because it completed a point-in-time recovery, pg_ctl used to report
a message that indicated a failure.  It's not really a failure, so
instead say "server shut down because of recovery target settings".

Zhao Junwang, Crisp Lee, Laurenz Albe

Discussion: https://postgr.es/m/CAGHPtV7GttPZ-HvxZuYRy70jLGQMEm5=LQc4fKGa=J74m2VZbg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/cd85ae1114fedcce8602bca77b4557fe75165637

Modified Files
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src/bin/pg_ctl/pg_ctl.c | 24 ++++++++++++++++++------
1 file changed, 18 insertions(+), 6 deletions(-)