Add hip support

[dacorvo]

What does this PR do?

This is a rebase of #280.

This has been tested on an AMD Instinct MI250X/MI250.

Some tests with qfloat8 Linear are failing because there is a wider mismatch between the quantized and non-quantized version, but this is a good first step.

FAILED test/nn/test_qlinear.py::test_quantize_linear_float16_activations_float8[cuda-a-qfloat8-e4m3-w-qint8-fp16-bias-10-256-1] - ValueError: Alignment 0.95751953 deviates too much from 1.0 with atol=0.005, rtol=0.001
FAILED test/nn/test_qlinear.py::test_quantize_linear_float16_activations_float8[cuda-a-qfloat8-e4m3-w-qint8-fp16-bias-10-256-10] - ValueError: Alignment 0.95556641 deviates too much from 1.0 with atol=0.005, rtol=0.001
FAILED test/nn/test_qlinear.py::test_quantize_linear_float16_activations_float8[cuda-a-qfloat8-e4m3-w-qint8-fp16-no-bias-10-256-1] - ValueError: Alignment 0.95458984 deviates too much from 1.0 with atol=0.005, rtol=0.001
FAILED test/nn/test_qlinear.py::test_quantize_linear_float16_activations_float8[cuda-a-qfloat8-e4m3-w-qint8-fp16-no-bias-10-256-10] - ValueError: Alignment 0.95507812 deviates too much from 1.0 with atol=0.005, rtol=0.001
FAILED test/nn/test_qlinear.py::test_quantize_linear_float16_activations_float8[cuda-a-float8-e4m3-uz-w-qint8-fp16-bias-10-256-1] - ValueError: Alignment 0.99267578 deviates too much from 1.0 with atol=0.005, rtol=0.001
FAILED test/nn/test_qlinear.py::test_quantize_linear_float16_activations_float8[cuda-a-float8-e4m3-uz-w-qint8-fp16-bias-10-256-10] - ValueError: Alignment 0.99316406 deviates too much from 1.0 with atol=0.005, rtol=0.001
FAILED test/nn/test_qlinear.py::test_quantize_linear_float16_activations_float8[cuda-a-float8-e4m3-uz-w-qint8-fp16-no-bias-10-256-1] - ValueError: Alignment 0.99267578 deviates too much from 1.0 with atol=0.005, rtol=0.001
FAILED test/nn/test_qlinear.py::test_quantize_linear_float16_activations_float8[cuda-a-float8-e4m3-uz-w-qint8-fp16-no-bias-10-256-10] - ValueError: Alignment 0.99267578 deviates too much from 1.0 with atol=0.005, rtol=0.001