contrib, libcpp, libstdc++: Update to Unicode 16.0

contrib, libcpp, libstdc++: Update to Unicode 16.0

It is autumn again and there is a new Unicode version 16.0.

The following patch updates our Unicode stuff in contrib, libcpp and
libstdc++ from that Unicode version.

2024-10-08  Jakub Jelinek  <jakub@redhat.com>

contrib/
	* unicode/README: Update glibc git commit hash, replace
	Unicode 15 or 15.1 versions with 16.
	* unicode/gen_libstdcxx_unicode_data.py: Use 160000 instead of
	150100 in _GLIBCXX_GET_UNICODE_DATA test.
	* unicode/from_glibc/utf8_gen.py: Updated from glibc
	064c708c78cc2a6b5802dce73108fc0c1c6bfc80 commit.
	* unicode/DerivedCoreProperties.txt: Updated from Unicode 16.0.
	* unicode/emoji-data.txt: Likewise.
	* unicode/PropList.txt: Likewise.
	* unicode/GraphemeBreakProperty.txt: Likewise.
	* unicode/DerivedNormalizationProps.txt: Likewise.
	* unicode/NameAliases.txt: Likewise.
	* unicode/UnicodeData.txt: Likewise.
	* unicode/EastAsianWidth.txt: Likewise.
gcc/testsuite/
	* c-c++-common/cpp/named-universal-char-escape-1.c: Add tests
	for some Unicode 16.0 characters, both normal and generated.
libcpp/
	* makeucnid.cc (write_copyright): Update Unicode Copyright years.
	* makeuname2c.cc (generated_ranges): Adjust Unicode version from 15.1
	to 16.0.  Add EGYPTIAN HIEROGLYPH- generated range, adjust indexes in
	following entries.
	(write_copyright): Update Unicode Copyright years.
	* generated_cpp_wcwidth.h: Regenerated.
	* ucnid.h: Regenerated.
	* uname2c.h: Regenerated.
libstdc++-v3/
	* include/bits/unicode.h (std::__unicode::__v15_1_0): Rename inline
	namespace to ...
	(std::__unicode::__v16_0_0): ... this.
	(_GLIBCXX_GET_UNICODE_DATA): Change from 150100 to 160000.
	* include/bits/unicode-data.h: Regenerated.
	* testsuite/ext/unicode/properties.cc: Check for _Gcb_SpacingMark
	on U+11F03 rather than U+1D16D as the latter lost SpacingMark property
	in Unicode 16.0.