[atomics.types.int] Use the terms "character type" and "standard integer type" instead of listing each type

Revised description of atomic class template specializations.

Author: eisenwave

source/threads.tex

@@ -4995,23 +4995,10 @@
 \indexlibrary{\idxcode{atomic<\placeholder{integral-type}>}}%
 \pnum
 There are specializations of the \tcode{atomic}
-class template for the integral types
-\tcode{char},
-\tcode{signed char},
-\tcode{unsigned char},
-\tcode{short},
-\tcode{unsigned short},
-\tcode{int},
-\tcode{unsigned int},
-\tcode{long},
-\tcode{unsigned long},
-\tcode{long long},
-\tcode{unsigned long long},
-\keyword{char8_t},
-\keyword{char16_t},
-\keyword{char32_t},
-\keyword{wchar_t},
-and any other types needed by the typedefs in the header \libheaderref{cstdint}.
+class template for
+each character type\iref{basic.fundamental},
+each standard integer type, and
+any other types needed by the typedefs in the header \libheaderref{cstdint}.
 For each such type \tcode{\placeholder{integral-type}}, the specialization
 \tcode{atomic<\placeholder{integral-type}>} provides additional atomic operations appropriate to integral types.
 \begin{note}