automation: include real-time view of the domU console log too

Passthrough domU console log to the serial console in real time, not
only after the test. First of all, this gives domU console also in case
of test failure. But also, allows correlation between domU and dom0 or
Xen messages.

To avoid ambiguity, add log prefix with 'sed'.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-acked-by: Henry Wang <Henry.Wang@arm.com>

automation/scripts/qubes-x86-64.sh

@@ -33,8 +33,6 @@ echo \"${passed}\"
 until grep -q \"${passed}\" /var/log/xen/console/guest-domU.log; do
     sleep 1
 done
-# get domU console content into test log
-tail -n 100 /var/log/xen/console/guest-domU.log
 echo \"${passed}\"
 "
 if [ "${test_variant}" = "dom0pvh" ]; then
@@ -59,8 +57,6 @@ echo deep > /sys/power/mem_sleep
 echo mem > /sys/power/state
 # now wait for resume
 sleep 5
-# get domU console content into test log
-tail -n 100 /var/log/xen/console/guest-domU.log
 xl list
 xl dmesg | grep 'Finishing wakeup from ACPI S3 state' || exit 1
 # check if domU is still alive
@@ -121,7 +117,6 @@ echo \"${passed}\"
 until grep -q \"^domU Welcome to Alpine Linux\" /var/log/xen/console/guest-domU.log; do
     sleep 1
 done
-tail -n 100 /var/log/xen/console/guest-domU.log
 "
 fi
 
@@ -169,6 +164,8 @@ ifconfig eth0 up
 ifconfig xenbr0 up
 ifconfig xenbr0 192.168.0.1
 
+# get domU console content into test log
+tail -F /var/log/xen/console/guest-domU.log 2>/dev/null | sed -e \"s/^/(domU) /\" &
 xl create /etc/xen/domU.cfg
 ${dom0_check}
 " > etc/local.d/xen.start