[clang] [Tooling/Inclusion] Update std symbol mapping (PR #118174)

[Vadim D. via cfe-commits]

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@@ -1241,8 +1254,7 @@ SYMBOL(fgetwc, None, <wchar.h>)
 SYMBOL(fgetws, std::, <cwchar>)
 SYMBOL(fgetws, None, <cwchar>)
 SYMBOL(fgetws, None, <wchar.h>)
-SYMBOL(filebuf, std::, <streambuf>)
-SYMBOL(filebuf, std::, <iostream>)
+SYMBOL(filebuf, std::, <fstream>)
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vvd170501 wrote:

Previous versions of cppreference mentioned incorrect headers for `filebuf` and `wfilebuf`.
`<fstream>` is the correct one: https://eel.is/c++draft/fstream.syn#lib:filebuf

https://github.com/llvm/llvm-project/pull/118174