bsp: Use `send-no-hostname` for Corstone-1000

We assume the board will always come up with the same IP address
in our setup if the lease on the DHCP server has not expired, but
this is not the case with Corstone-1000 MPS3.

It is been observed, we have two IP address leases, one lease with just
a MAC address identifier when it boots into recovery/firmware and other
with a MAC address and a host name when the Cassini distro boots up.

The DHCP servers are configured this way and are outside
of our control.

Therefore, when the Cassini distro boots, we configure
systemd network to request an IP address without a host name, which
should give out the old leased IP address from the DHCP server.

Signed-off-by: Vikas Katariya <vikas.katariya@arm.com>