Add uint8 support for quantized conv2d NHWC and enable per_tensor_out operator

[khazaei]

Summary:
Goal is to get the fallback path working first then add ties. Before this change the tests were not passing.

Added support for uint8 (UWORD8) data type in quantized_conv2d_nhwc_out for both standard and depthwise convolutions on HiFi backends. This change:

• Extends op_quantized_conv2d_nhwc_out.cpp with uint8 handling for conv2d and depthwise conv2d operations using xa_nn_conv2d_per_chan_sym8sxasym8s and xa_nn_conv2d_depthwise_asym8uxasym8u kernels
• Enables the cadence::quantized_conv2d_nhwc.per_tensor_out operator mapping in operator_fallback.bzl for both HiFi and TIE backends
• Updates BUCK dependencies for TIE operators to include required exec_aten and kernel_runtime_context libs
• Modifies test configuration to run on Artemis_HiFi4_UT_v3 backend
• Fixed out_data_format for NHWC (was using NCHW format 1, should be 0)
• Added weight transpose for depthwise conv (NHWC weight [OC,KH,KW,1] → nnlib expected [KH,KW,OC])

Differential Revision: D97036131

[pytorch-bot]

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[meta-codesync]

@khazaei has exported this pull request. If you are a Meta employee, you can view the originating Diff in D97036131.

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