arc: Add a custom overlay

Add an overlay that does many nice things:
1. Includes touch screen calibration
2. Configures input for Qt
3. Configures inetd to accept connectiosn for ftpd & telnetd
4. Configures eth0 for nSIM SystemC model
5. Mounts NFS share on host
6. Reconfigures inittab, to avoid getty
7. Configures DNS servers

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
arc: Enable telnetd and ftpd

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
arc: Use new overlay in configs

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>