[libcxx] don't `#include <cwchar>` if wide chars aren't enabled (#99911)

Pull request #96032 unconditionall adds the `cwchar` include in the
`format` umbrella header. However support for wchar_t can be disabled in
the build system (LIBCXX_ENABLE_WIDE_CHARACTERS).

This patch guards against inclusion of `cwchar` in `format` by checking
the `_LIBCPP_HAS_NO_WIDE_CHARACTERS` define.

For clarity I've also merged the include header section that `cwchar`
was in with the one above as they were both guarded by the same `#if`
logic.

0 files changed, 0 insertions, 0 deletions