Improve ROCm support. (#780)

- updates to support ROCm 5.2
- workarounds in tests where NV tools were used unconditionally
- implemented `get_num_blocks()` and `add_memfence()` for AMD GPU
- backported from history some atomics
- added bf16 support
- minor warnings cleanup
- added dockerfile to run on a ROCm enabled machine

Co-authored-by: B1tway <andrew.shukshov@gmail.com>
Co-authored-by: Andrey Shukshov <36711069+B1tway@users.noreply.github.com>

python/test/unit/language/test_core.py

@@ -369,9 +369,6 @@ def test_atomic_rmw(op, dtype_x, mode, device='cuda'):
     ('float32', 'int32', True)
 ])
 def test_cast(dtype_x, dtype_z, bitcast, device='cuda'):
-    if torch.version.hip is not None:
-        assert 'bfloat' not in dtype_x 
-        assert 'bfloat' not in dtype_z
 
     SIZE = 1024
     x = triton.testing.random((SIZE, ), dtype=cvt[dtype_x], device=device)