[libc++] Make parameter names consistent and enforce the naming style using readability-identifier-naming

Ensure that parameter names have the style `__lower_case`

Reviewed By: ldionne, #libc

Spies: aheejin, sstefan1, libcxx-commits, miyuki

Differential Revision: https://reviews.llvm.org/D129051

NOKEYCHECK=True
GitOrigin-RevId: b48c5010a46246cc3337244f7e2736dacf5889dc
diff --git a/include/exception b/include/exception
index 955739e..7b514e5 100644
--- a/include/exception
+++ b/include/exception
@@ -216,7 +216,7 @@
 
 _LIBCPP_FUNC_VIS exception_ptr __copy_exception_ptr(void *__except, const void* __ptr);
 _LIBCPP_FUNC_VIS exception_ptr current_exception() _NOEXCEPT;
-_LIBCPP_NORETURN _LIBCPP_FUNC_VIS void rethrow_exception(exception_ptr p);
+_LIBCPP_NORETURN _LIBCPP_FUNC_VIS void rethrow_exception(exception_ptr);
 
 // This is a built-in template function which automagically extracts the required
 // information.