[clang] [git-clang-format] add fallback style argument option (PR #137609)

[Owen Pan via cfe-commits]

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@@ -189,6 +189,13 @@ def main():
         default=config.get("clangformat.style", None),
         help="passed to clang-format",
     ),
+    p.add_argument(
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owenca wrote:

Please move this to just before `--force` to keep the options sorted. (We can also move `--diff_from_common_commit` up now or in another patch.)

https://github.com/llvm/llvm-project/pull/137609