KVM: selftests: Fix an off-by-one in the number of dirty_log_test iterations

Actually run all requested iterations, instead of iterations-1 (the count
starts at '1' due to the need to avoid '0' as an in-memory value for a
dirty page).

Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Link: https://lore.kernel.org/r/20250111003004.1235645-20-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: sean-jc

tools/testing/selftests/kvm/dirty_log_test.c

@@ -695,7 +695,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 
 	pthread_create(&vcpu_thread, NULL, vcpu_worker, vcpu);
 
-	for (iteration = 1; iteration < p->iterations; iteration++) {
+	for (iteration = 1; iteration <= p->iterations; iteration++) {
 		unsigned long i;
 
 		sync_global_to_guest(vm, iteration);