Improve guard for triton compatibility (#1497)

bitsandbytes/triton/triton_utils.py

-import importlib
+import functools
 
 
+@functools.lru_cache(None)
 def is_triton_available():
-    return importlib.util.find_spec("triton") is not None
+    try:
+        # torch>=2.2.0
+        from torch.utils._triton import has_triton, has_triton_package
+
+        return has_triton_package() and has_triton()
+    except ImportError:
+        from torch._inductor.utils import has_triton
+
+        return has_triton()