T5901: Add DHCP base_path dir during first boot

We should create dhclient base_path dir /run/dhclient during the
first boot.

It fixes cloud-init boot issues

/etc/dhcp/dhclient-exit-hooks.d/03-vyos-dhclient-hook: line 33: /run/dhclient/dhclient_eth0.lease: No such file or directory