Bug fix and optimisation for persistent reduction kernel tuning

Original PR had incorrect indentation. Updated PR such that autotune will always add tiny configs, otherwise use the hinted configs only.

Author: jataylo

torch/_inductor/runtime/triton_heuristics.py

@@ -2595,20 +2595,20 @@ def _persistent_reduction_configs(
         elif reduction_hint == ReductionHint.OUTER:
             configs = configs[-1:]
 
-    if reduction_hint == ReductionHint.OUTER_TINY:
-        tiny_configs = [
-            triton_config_reduction(
-                size_hints,
-                2 * (256 // rnumel) if rnumel <= 256 else 1,
-                rnumel,
-            )
-        ]
-        if max_autotune_enabled:
-            for tconfig in tiny_configs:
-                if tconfig not in configs:
-                    configs.append(tconfig)
-            else:
-                configs = tiny_configs
+    tiny_configs = [
+        triton_config_reduction(
+            size_hints,
+            2 * (256 // rnumel) if rnumel <= 256 else 1,
+            rnumel,
+        )
+    ]
+
+    if max_autotune_enabled:
+        for conf in tiny_configs:
+            if conf not in configs:
+                configs.append(conf)
+    elif reduction_hint == ReductionHint.OUTER_TINY:
+        configs = tiny_configs
 
     for c in configs:
         # we don't need Rn_BLOCK for persistent reduction