pgsql: Refactor to introduce pg_locale_deterministic().

Refactor to introduce pg_locale_deterministic().

Avoids the need of callers to test for NULL, and also avoids the need
to access the pg_locale_t structure directly.

Reviewed-by: Peter Eisentraut, Peter Geoghegan
Discussion: https://postgr.es/m/a581136455c940d7bd0ff482d3a2bd51af25a94f.camel%40j-davis.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/6974a8f7682beeb515b78b34a5253d5f96552f58

Modified Files
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src/backend/access/hash/hashfunc.c |  4 ++--
src/backend/regex/regc_pg_locale.c |  2 +-
src/backend/utils/adt/like.c       |  4 ++--
src/backend/utils/adt/pg_locale.c  |  9 +++++++++
src/backend/utils/adt/varchar.c    |  8 ++++----
src/backend/utils/adt/varlena.c    | 14 ++++++--------
src/include/utils/pg_locale.h      |  1 +
7 files changed, 25 insertions(+), 17 deletions(-)