The option was added so that the qemurunner could start a second tcp
serial port without adding machine conditional logic to qemurunner.
The issue that made this necessary was that when "virt" is passed to
qemu-system-aarch64, the normal mechanism for specifying a tcp serial
port does not work. This is because the hardware for the "virt" machine
is hardcoded in the device tree blob and the addition devices must be
virtio devices.
So runqemu can specify virtio for qemuarm64 whereas it seems all other
qemu machines work with the "-serial tcp*" option.
Signed-off-by: Randy Witt <randy.e.witt@linux.intel.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
