pgsql: Use C11 char16_t and char32_t for Unicode code points.

Use C11 char16_t and char32_t for Unicode code points.

Reviewed-by: Tatsuo Ishii <ishii(at)postgresql(dot)org>
Reviewed-by: Thomas Munro <thomas(dot)munro(at)gmail(dot)com>
Reviewed-by: Peter Eisentraut <peter(at)eisentraut(dot)org>
Discussion: https://postgr.es/m/bedcc93d06203dfd89815b10f815ca2de8626e85.camel%40j-davis.com

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/3853a6956c3e3bc7a6fa9bcdb205a2997f46bac2

Modified Files
--------------
configure | 2 +-
configure.ac | 1 +
meson.build | 1 +
src/backend/parser/parser.c | 8 ++--
src/backend/parser/scan.l | 8 ++--
src/backend/utils/adt/jsonpath_scan.l | 6 +--
src/backend/utils/adt/pg_locale_builtin.c | 44 +++++++++++------
src/backend/utils/adt/varlena.c | 40 ++++++++--------
src/backend/utils/mb/mbutils.c | 4 +-
src/common/saslprep.c | 48 +++++++++----------
src/common/unicode/case_test.c | 23 ++++-----
src/common/unicode/category_test.c | 3 +-
src/common/unicode/generate-norm_test_table.pl | 4 +-
src/common/unicode/generate-unicode_case_table.pl | 7 ++-
.../unicode/generate-unicode_category_table.pl | 8 ++--
src/common/unicode/norm_test.c | 6 +--
src/common/unicode_case.c | 56 +++++++++++-----------
src/common/unicode_category.c | 50 +++++++++----------
src/common/unicode_norm.c | 56 +++++++++++-----------
src/fe_utils/mbprint.c | 10 ++--
src/include/c.h | 23 +++++++++
src/include/common/unicode_case.h | 10 ++--
src/include/common/unicode_case_table.h | 13 +++--
src/include/common/unicode_category.h | 46 +++++++++---------
src/include/common/unicode_category_table.h | 8 ++--
src/include/common/unicode_norm.h | 6 +--
src/include/mb/pg_wchar.h | 32 ++++++-------
src/include/pg_config.h.in | 3 ++
src/tools/pgindent/typedefs.list | 2 +
29 files changed, 284 insertions(+), 244 deletions(-)