KVM: selftests: Allow running a single iteration of dirty_log_test

Now that dirty_log_test doesn't require running multiple iterations to
verify dirty pages, and actually runs the requested number of iterations,
drop the requirement that the test run at least "3" (which was really "2"
at the time the test was written) iterations.

Link: https://lore.kernel.org/r/20250111003004.1235645-21-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: sean-jc

tools/testing/selftests/kvm/dirty_log_test.c

@@ -886,7 +886,7 @@ int main(int argc, char *argv[])
 		}
 	}
 
-	TEST_ASSERT(p.iterations > 2, "Iterations must be greater than two");
+	TEST_ASSERT(p.iterations > 0, "Iterations must be greater than zero");
 	TEST_ASSERT(p.interval > 0, "Interval must be greater than zero");
 
 	pr_info("Test iterations: %"PRIu64", interval: %"PRIu64" (ms)\n",