Small windows-related cleanup for third_party/nvidia/backend/driver.py (#2937)

Part of #2824

One import was duplicated, the other is not used.

Signed-off-by: Anatoly Myachev <[email protected]>

Author: anmyachev

third_party/nvidia/backend/driver.py

@@ -2,10 +2,8 @@
 import os
 import sysconfig
 import hashlib
-import sysconfig
 import subprocess
 import tempfile
-import sys
 from pathlib import Path
 from triton.runtime.build import _build
 from triton.runtime.cache import get_cache_manager