pgsql: doc: Fix description of configure --with-icu option

doc: Fix description of configure --with-icu option

It was claiming that the ICU locale provider is used by default, which
is not correct.  (From commit fcb21b3acdc; it was once contemplated to
make it the default, but it wouldn't have been part of that patch in
any case.)

Reviewed-by: Kashif Zeeshan <kashi.zeeshan@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/a71023c2-0ae0-45ad-9688-cf3b93d0d65b%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9c1d1bde4487a40e963a9571ee44c90deea71f82

Modified Files
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doc/src/sgml/installation.sgml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)