* m4/glibc2.m4, m4/glibc21.m4, m4/intdiv0.m4, m4/intmax.m4: Remove.
* m4/inttypes-h.m4, m4/inttypes-pri.m4, m4/inttypes.m4: Remove.
* m4/inttypes_h.m4, m4/isc-posix.m4, m4/lcmessage.m4: Remove.
* m4/lib-ld.m4, m4/lib-link.m4, m4/lib-prefix.m4: Remove.
* m4/longdouble.m4, m4/longlong.m4, m4/nls.m4, m4/po.m4: Remove.
* m4/printf-posix.m4, m4/progtest.m4, m4/signed.m4: Remove.
* m4/size_max.m4, m4/stdint_h.m4, m4/uintmax_t.m4: Remove.
* m4/ulonglong.m4, m4/visibility.m4, m4/wchar_t.m4: Remove.
* m4/wint_t.m4, m4/xsize.m4: Remove.