Add missing config.DISABLE_PERFORMANCE_WARNINGS checks

Fix a few functions that raise a NumbaPerformanceWarning` without
checking whether `config.DISABLE_PERFORMANCE_WARNINGS` is set.

Author: maxkapur

numba_cuda/numba/cuda/cudadrv/devicearray.py

@@ -876,7 +876,10 @@ def auto_device(obj, stream=0, copy=True, user_explicit=False):
             sentry_contiguous(obj)
             devobj = from_array_like(obj, stream=stream)
         if copy:
-            if config.CUDA_WARN_ON_IMPLICIT_COPY:
+            if (
+                config.CUDA_WARN_ON_IMPLICIT_COPY
+                and not config.DISABLE_PERFORMANCE_WARNINGS
+            ):
                 if (
                     not user_explicit and
                     (not isinstance(obj, DeviceNDArray)

numba_cuda/numba/cuda/dispatcher.py

@@ -519,7 +519,10 @@ def __init__(self, dispatcher, griddim, blockdim, stream, sharedmem):
         self.stream = stream
         self.sharedmem = sharedmem
 
-        if config.CUDA_LOW_OCCUPANCY_WARNINGS:
+        if (
+            config.CUDA_LOW_OCCUPANCY_WARNINGS
+            and not config.DISABLE_PERFORMANCE_WARNINGS
+        ):
             # Warn when the grid has fewer than 128 blocks. This number is
             # chosen somewhat heuristically - ideally the minimum is 2 times
             # the number of SMs, but the number of SMs varies between devices -