fix a clear nofile limit cache error in syscall.prlimit

Signed-off-by: lifubang <[email protected]>

Author: lifubang

src/syscall/syscall_linux.go

@@ -1289,7 +1289,7 @@ func Munmap(b []byte) (err error) {
 // This is unexported but can be called from x/sys/unix.
 func prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) {
 	err = prlimit1(pid, resource, newlimit, old)
-	if err == nil && newlimit != nil && resource == RLIMIT_NOFILE {
+	if err == nil && newlimit != nil && resource == RLIMIT_NOFILE && (pid == 0 || pid == Getpid()) {
 		origRlimitNofile.Store(nil)
 	}
 	return err