torture: Make kvm-series.sh give run numbers and totals

torture: Make kvm-series.sh give run numbers and totals

The kvm-series.sh script can easily be convinced to run on the order of
1,000 guest OSes, so some sort of progress indicator would be helpful.
This commit therefore updates the "Starting" output lines to read as in
the following example, adding the ("3 of 4"):

Starting TREE02/1.7e0ad1b49057 using 8 CPUs (4 of 4) Sat Nov 8 10:51:06 PM PST 2025

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>