More API Compat Fixes

[123epsilon]

This contributes the following:

• Implement torch.tensor.add
• Implement torch.tensor.norm - this resolves the expected test case's API issue (NormalizeModule_basic) but results in an IR failure due to some additional pass in torch-mlir lowering the torch.aten.norm.ScalarOpt_dim to torch.aten.linalg_vector_norm using the operand value, however we match the raw IR so I added this to xfails, as it is functionally the same.
• Added back the permute pybind to autogeneration script and addressed some failing cases for permute due to the precedence of the *args signature, adding back the original pybind is still necessary to handle the case where dims is passed by keyword
• Change the base class for the layout and memory_layout enum classes to IntEnum so that they can be readily converted to integers where necessary, this resolves issues of the type:

1 : ElementwiseCloneChannelsLastMemoryFormatModule_basic
 clone(): incompatible function arguments. The following argument types are supported:
     1. (self: pi.mlir._mlir_libs._pi_mlir.Tensor, memory_format: pi.mlir._mlir_libs._pi_mlir.AnyTorchOptionalIntValue = None, *, loc: mlir.ir.Location = None, ip: mlir.ir.InsertionPoint = None) -> pi.mlir._mlir_libs._pi_mlir.Tensor

 Invoked with: Tensor(<block argument> of type '!torch.tensor' at index: 0); kwargs: memory_format=<memory_format.channels_last: 2>

While this last change does resolve a number of test cases, it is worth noting that for one case: ToDtypeLayoutStridedModule_basic the API failure is resolved but the case still fails due to:

Failure while executing pass pipeline:
error: unknown: found an op that was marked as backend illegal
note: unknown: see current operation: %4 = "torch.aten.to.dtype_layout"(%arg0, %3, %2, %1, %1, %0, %0, %1) : (!torch.vtensor<[?,?],f32>, !torch.int, !torch.int, !torch.none, !torch.none, !torch.bool, !torch.bool, !torch.none) -> !torch.vtensor<[?,?],f64>
note: unknown: this is likely due to DecomposeComplexOps being unable to decompose this op

emitted from here

I couldn't find a decomposition for this op (aten.to.dtype_layout) in DecomposeComplexOps.cpp so this may be something missing from torch-mlir, but if its better to remove it from the PR that's fine too - this is only relevant to changing the layout enum. @makslevental

[brucekimrokcmu]

LGTM!

[makslevental]