torture: Make kvm.sh "--dryrun sched" summarize number of builds

Knowing the number of builds that kvm.sh will split a run into allows
estimation of the duration of a test, give or take build duration.
This commit therefore adds a line of output to "--dryrun sched" that
gives the number of builds that will be run.  This excludes "builds"
for repeated scenarios that reuse an earlier build.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

tools/testing/selftests/rcutorture/bin/kvm.sh

@@ -536,6 +536,10 @@ then
 	egrep 'Start batch|Starting build\.' $T/script |
 		grep -v ">>" |
 		sed -e 's/:.*$//' -e 's/^echo //'
+	nbuilds="`grep 'Starting build\.' $T/script |
+		  grep -v ">>" | sed -e 's/:.*$//' -e 's/^echo //' |
+		  awk '{ print $1 }' | grep -v '\.' | wc -l`"
+	echo Total number of builds: $nbuilds
 	nbatches="`grep 'Start batch' $T/script | grep -v ">>" | wc -l`"
 	echo Total number of batches: $nbatches
 	exit 0