fix example input generation for dynamic shapes (#4207)

Summary:
Pull Request resolved: #4207

Dynamic input shapes minimum bound occaisonally generates 0, which is not a valid input shape. This change fixes that bug

Reviewed By: kirklandsign

Differential Revision: D59617219

fbshipit-source-id: 9c6c8bc136dcacf0bc6d80835d31892aba7e90a7

Author: mcr229

backends/xnnpack/test/tester/tester.py

@@ -437,7 +437,7 @@ def fn(x):
                             dim_spec.max, 1000
                         )  # unbounded int max is too large
                         lower_bound = (
-                            dim_spec.min if dim_spec.min != 2 else 1
+                            dim_spec.min if dim_spec.min >= 2 else 1
                         )  # 0/1 specialization means dim_spec.min can never be 1
                         dim_name_to_size[dim_name] = fn(
                             random.randint(lower_bound, upper_bound)