Arm backend: Refactor SliceCopySupport

Refactor SliceCopySupport to not use TosaArg, but to use torch.fx.Node
instead.

Signed-off-by: Oscar Andersson <[email protected]>
Change-Id: I1d67161d017a5e70348fa1aeaa0857041274bc6d

Author: oscarandersson8218

backends/arm/operator_support/slice_copy_support.py

@@ -12,7 +12,6 @@
     SupportedTOSAOperatorCheck,
 )
 from executorch.backends.arm.tosa_specification import TosaSpecification
-from executorch.backends.arm.tosa_utils import getNodeArgs
 from executorch.exir.dialects._ops import ops as exir_ops
 
 logger = logging.getLogger(__name__)
@@ -33,8 +32,8 @@ def is_node_tosa_supported(self, node: fx.Node, tosa_spec: TosaSpecification) ->
         if tosa_spec not in self.tosa_specs:
             return False
 
-        inputs = getNodeArgs(node)
-        if len(inputs) == 5 and (step := inputs[4].number) != 1:
+        args = node.args
+        if len(args) == 5 and (step := args[4]) != 1:
             logging.warning(f"{node.target} with step size of {step} not supported.")
             return False
         return True