Include sendfile64() for Linux

Author: nroi

src/unix/linux_like/linux/mod.rs

@@ -3230,6 +3230,12 @@ extern "C" {
         offset: *mut off_t,
         count: ::size_t,
     ) -> ::ssize_t;
+    pub fn sendfile64(
+        out_fd: ::c_int,
+        in_fd: ::c_int,
+        offset: *mut off64_t,
+        count: ::size_t,
+    ) -> ::ssize_t;
     pub fn sigsuspend(mask: *const ::sigset_t) -> ::c_int;
     pub fn getgrgid_r(
         gid: ::gid_t,