fix: semaphore cbindgen use [export] exclude to avoid [fn] duplicate

src/header/semaphore/cbindgen.toml

@@ -15,9 +15,7 @@ style = "Type"
 no_includes = true
 cpp_compat = true
 
-[fn]
-# cbindgen cannot emit variadic functions automatically; write the sem_open
-# prototype by hand in the trailer so C callers see the POSIX signature.
+[export]
 exclude = ["sem_open"]
 
 [enum]