pgsql: Allow initdb to complete on systems without "locale" command

Allow initdb to complete on systems without "locale" command

This partially reverts 2fe3bdbd691a5d11626308e7d660440be6c210c8, which
added an error check on the "locale -a" execution.  This is removed
again, adding a comment explaining why.  We already had code that
shows a warning if no system locales could be found, which should be
sufficient for feedback to the user.

Discussion: https://www.postgresql.org/message-id/flat/b2b491d1-3b36-15b9-6910-5b5540b27f5c%40enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/af3abca029b39ae6bdb683a758b11375e9839631

Modified Files
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src/backend/commands/collationcmds.c | 17 +++++++----------
1 file changed, 7 insertions(+), 10 deletions(-)