win32 remove deprecated winapi part

Author: devnexen

libc-test/semver/windows-msvc-x86_64.txt

@@ -18,12 +18,3 @@ extern "C" {
         count: ::size_t,
     ) -> *mut ::c_void;
 }
-
-cfg_if! {
-    if #[cfg(target_arch = "x86_64")] {
-        mod x86_64;
-        pub use self::x86_64::*;
-    } else {
-        // Unknown target_arch
-    }
-}