pgsql: Revert ill-considered change in pg_resetwal output.

Revert ill-considered change in pg_resetwal output.

Commit 31dcfae83 changed one pg_resetwal output string, and a
corresponding test in pg_upgrade, without sufficient thought for
the consequences.  We can't change that output without creating
hazards for cross-version upgrades, since pg_upgrade needs to be able
to read the output of several different versions of pg_resetwal.
There may well be external tools with the same requirement.

For the moment, just revert those two changes.  What we really
ought to do here is have a separate, stable, easily machine-readable
output format for pg_resetwal and pg_controldata, as proposed
years ago by Alvaro.  Once that's in place and tools no longer
need to depend on the exact spelling of the human-readable output,
we can put back this change.

Discussion: https://postgr.es/m/fbea8c6f-415a-bad9-c3de-969c40d08a84@dunslane.net

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/918de37652138da7f7e54c79351178367d60f501

Modified Files
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src/bin/pg_resetwal/pg_resetwal.c | 2 +-
src/bin/pg_upgrade/controldata.c  | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)