Fix the cuda.is_supported_version() API

PR #313 removed the `runtime.is_supported_version()` API, but it is used
by the `cuda.is_supported_version()` public API. This commit restores
the `cuda.is_supported_version()` API by checking whether the CUDA
runtime major version is 12 or 13.

The version number check will need bumping as appropriate when future
toolkit major versions are added and existing toolkit major version are
dropped. This situation will be caught by the test that is added to
exercise this API.

Author: gmarkall

numba_cuda/numba/cuda/device_init.py

@@ -133,7 +133,7 @@ def is_supported_version():
     - Generating an error or otherwise preventing the use of CUDA.
     """
 
-    return runtime.is_supported_version()
+    return runtime.get_version()[0] in (12, 13)
 
 
 def cuda_error():

numba_cuda/numba/cuda/tests/cudadrv/test_runtime.py

@@ -43,6 +43,16 @@ def test_visible_devices_set_after_import(self):
         visible_gpu_count = future.result()
         assert visible_gpu_count == 1
 
+    def test_is_supported_version(self):
+        # Exercise the `cuda.is_supported_version()` API.
+        #
+        # Assume for the purpose of the test that we're running on a supported
+        # toolkit version; if not, there's not much point in running the test
+        # suite.
+        from numba import cuda
+
+        self.assertTrue(cuda.is_supported_version())
+
 
 if __name__ == "__main__":
     unittest.main()