xla

a3b0c6ec - Lower quant/dequant torch op to StableHLO (#5763)

Lower quant/dequant torch op to StableHLO (#5763) (de)quantize_per_tensor/channel ops from PT2E quantization workflow are lowered to stablehlo uniform_dequantize/quantize. --------- Co-authored-by: Siyuan Liu <lsiyuan@google.coim>