LLVM: please add include-style in your example

[lidaobing]

https://llvm.org/docs/CodingStandards.html#include-style

Immediately after the header file comment (and include guards if working on a header file), the minimal list of #includes required by the file should be listed. We prefer these #includes to be listed in this order:

1. Main Module Header
2. Local/Private Headers
3. LLVM project/subproject headers (clang/..., lldb/..., llvm/..., etc)
4. System #includes

and each category should be sorted lexicographically by the full path.

[motine]

hey li, this is a great catch. thanks! would you be able to prepare a merge request to fix the issue? if you have trouble with it please let me know and i can assist.