pgsql: Add pg_iswxdigit(), useful for tsearch.

Add pg_iswxdigit(), useful for tsearch.

Reviewed-by: Peter Eisentraut <peter@eisentraut.org>
Discussion: https://postgr.es/m/0151ad01239e2cc7b3139644358cf8f7b9622ff7.camel@j-davis.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/67a8b49e96caf0782b556521c8d6650e78f2d88e

Modified Files
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src/backend/utils/adt/pg_locale.c         | 12 ++++++++++++
src/backend/utils/adt/pg_locale_builtin.c |  7 +++++++
src/backend/utils/adt/pg_locale_icu.c     |  7 +++++++
src/backend/utils/adt/pg_locale_libc.c    | 23 +++++++++++++++++++++++
src/include/utils/pg_locale.h             |  2 ++
5 files changed, 51 insertions(+)