[modules] Move ConvertUTF.h to a separate submodule that doesn't require C++.
The former setup once resulted in us ignoring the module for C compilations,
but Clang now errors on this if the header is included from C code (which it is).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@247377 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed