PR libstdc++/86008 add std::quoted support for string_view

PR libstdc++/86008 add std::quoted support for string_view

	PR libstdc++/86008
	* include/bits/quoted_string.h (_Quoted_string<basic_string_view, C>):
	Define new partial specialization.
	* include/std/iomanip (quoted(basic_string_view<C,T>, C, C)): Define
	new overload.
	(operator<<(basic_ostream<C,T>&, const _Quoted_string<S,C>&)): Use
	value not reference for iteration.
	* testsuite/27_io/manipulators/standard/char/quoted.cc: Adjust
	comment.
	* testsuite/27_io/manipulators/standard/char/quoted_sv.cc: New test.
	* testsuite/27_io/manipulators/standard/wchar_t/quoted.cc: Adjust
	comment.

From-SVN: r261227