[TVMC] Tune each AutoTVM tasks at least once

Author: PhilippvK

python/tvm/driver/tvmc/autotuner.py

@@ -591,7 +591,7 @@ def tune_model(
 
             # In autotvm, trials is specified per task. We can convert the per-model input
             # provided to per-task trials by dividing by the number of tasks.
-            trials = int(trials / max(len(tasks), 1))
+            trials = int(max(1, trials / max(len(tasks), 1)))
             logger.info("Autotuning with %d trials per task.", trials)
 
             tuning_options = {