pgsql: Improve error message about valid value for distance in phrase o

Improve error message about valid value for distance in phrase operator.

The distance in phrase operator must be an integer value between zero
and MAXENTRYPOS inclusive. But previously the error message about
its valid value included the information about its upper limit
but not lower limit (i.e., zero). This commit improves the error message
so that it also includes the information about its lower limit.

Back-patch to v9.6 where full-text phrase search was supported.

Author: Kyotaro Horiguchi
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/20210819.170315.1413060634876301811.horikyota.ntt@gmail.com

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/5d1c36fd204bc680745263c3f9f41978b368fa0a

Modified Files
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src/backend/utils/adt/tsquery.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)