add simple script to print controlsd alive and valid

selfdrive/debug/internal/check_alive_valid.py

@@ -0,0 +1,21 @@
+#!/usr/bin/env python3
+import time
+import cereal.messaging as messaging
+
+
+if __name__ == "__main__":
+  sm = messaging.SubMaster(['thermal', 'health', 'model', 'liveCalibration', 'dMonitoringState', 'plan', 'pathPlan'])
+
+
+  i = 0
+  while True:
+    sm.update(0)
+
+
+    i += 1
+    if i % 100 == 0:
+      print()
+      print("alive", sm.alive)
+      print("valid", sm.valid)
+
+    time.sleep(0.01)