Return error from settimes for vxworks

Author: B I Mohammed Abbas

library/std/src/sys/pal/unix/fs.rs

@@ -1327,7 +1327,7 @@ impl File {
             None => Ok(libc::timespec { tv_sec: 0, tv_nsec: libc::UTIME_OMIT as _ }),
         };
         cfg_if::cfg_if! {
-            if #[cfg(any(target_os = "redox", target_os = "espidf", target_os = "horizon"))] {
+            if #[cfg(any(target_os = "redox", target_os = "espidf", target_os = "horizon", target_os = "vxworks"))] {
                 // Redox doesn't appear to support `UTIME_OMIT`.
                 // ESP-IDF and HorizonOS do not support `futimens` at all and the behavior for those OS is therefore
                 // the same as for Redox.