Update statically linked libseccomp to 2.3.0
Fixes #20550
This update to libseccomp supports the new versions of socket
system calls that can be called directly rather than via the
socketcall syscall in kernel versions 4.3 or later with new glibc.
Note this library version now supports s390x and ppc64le, so
seccomp can be potentially be enabled for these architectures now.
Signed-off-by: Justin Cormack <justin.cormack@docker.com>