pgsql: Improve log messages from pg_import_system_collations().

Improve log messages from pg_import_system_collations().

pg_import_system_collations() was a bit inconsistent about how it
reported locales (names output by "locale -a") that it didn't make
pg_collation entries for. IMV we should print some suitable message
for every locale that we reject, except when it matches a pre-existing
pg_collation entry. (This is all at DEBUG1 log level, though, so as
not to create noise during initdb.) Add messages for the two cases
that were previously not logged, namely unrecognized encoding and
client-only encoding. Re-word the existing messages to have a
consistent style.

Anton Voloshin and Tom Lane

Discussion: https://postgr.es/m/429d64ee-188d-3ce1-106a-53a8b45c4fce@postgrespro.ru

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/69e31d05b0a33f55aa5d9540917540f5fccb93a7

Modified Files
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src/backend/commands/collationcmds.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)