Fix bug with block pointer multi dim args (#120263)
Summary:
Now we can parse statements like
```
%22 = tt.make_tensor_ptr %20, [%21, %c128_i64], [%c2048_i64, %c1_i64], [%1, %c0_i32]
```
Test Plan:
Added new test
```
buck2 test mode/opt //hammer/ops/tests/inductor:ragged_hstu_test
```
now passes again with optimizations
Differential Revision: D53975130
Pull Request resolved: https://github.com/pytorch/pytorch/pull/120263
Approved by: https://github.com/aakhundov, https://github.com/sijiac
