seccomp: allow sendto for vsock thread

as of rust 1.90, writes to unix socket streams use send_with_flags
instead of write, so it uses a sendto syscall instead of write.

Signed-off-by: Matt Moriarity <matt@mattmoriarity.com>

virtio-devices/src/seccomp_filters.rs

@@ -239,6 +239,7 @@ fn virtio_vsock_thread_rules() -> Vec<(i64, Vec<SeccompRule>)> {
         (libc::SYS_connect, vec![]),
         (libc::SYS_ioctl, create_vsock_ioctl_seccomp_rule()),
         (libc::SYS_recvfrom, vec![]),
+        (libc::SYS_sendto, vec![]),
         (libc::SYS_socket, vec![]),
         // If debug_assertions is enabled, closing a file first checks
         // whether the FD is valid with fcntl.