[libc++][format] Adds char formatter.
Implements the formatter for all fundamental integer types.
[format.formatter.spec]/2.1
The specializations
```
template<> struct formatter<char, char>;
template<> struct formatter<char, wchar_t>;
template<> struct formatter<wchar_t, wchar_t>;
```
This removes the stub implemented in D96664.
Implements parts of:
- P0645 Text Formatting
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D103466
NOKEYCHECK=True
GitOrigin-RevId: 49e736d845d8e1beb3db0abcc782c9525e44f31e
diff --git a/include/module.modulemap b/include/module.modulemap
index f7c3058..4f10773 100644
--- a/include/module.modulemap
+++ b/include/module.modulemap
@@ -450,6 +450,7 @@
module format_parse_context { private header "__format/format_parse_context.h" }
module format_string { private header "__format/format_string.h" }
module formatter { private header "__format/formatter.h" }
+ module formatter_char { private header "__format/formatter_char.h" }
module formatter_integer { private header "__format/formatter_integer.h" }
module formatter_integral { private header "__format/formatter_integral.h" }
module formatter_string { private header "__format/formatter_string.h" }