`iree-opt` does not properly include backend (`amdgpu`) dependent dialect for standalone (`iree-gpu-lower-ops`) pass

### What happened?

For end to end compilation with a simple batch gemm test case, I am able to confirm the test case can compile to finish. In order to observe what `iree-gpu-lower-ops` does (around how it lower a `multi_mma` op to `mfma` op), I intercepted the IR and manually compile it via `iree-opt`.

`iree-opt` ended up crashing with error code:
> LLVM ERROR: Building op amdgpu.mfma but it isn't known in this MLIRContext: the dialect may not be loaded or this operation hasn't been added by the dialect.

Upon investigation, a few evidence indicate that this shouldn't happen, including:
1. `iree-opt --show-dialects` indeed print amdgpu as part of the available dialects.
2. `iree-opt --allow-unregistered-dialect` cannot prevent the pass from crashing `iree-opt`
3. Observe that `registerAllDialects(registry)` is already invoked from `iree-opt` per https://github.com/iree-org/iree/blob/3acb533ca5d5f57729f492b8fd8533765be31923/compiler/src/iree/compiler/API/Internal/IREEOptToolEntryPoint.cpp#L148
- Manually add `registry.insert();` will continue to yield a crash from `iree-opt`
4. What ended up fixing the the crash is via including `amdgpu` dialect as a dependency at: https://github.com/iree-org/iree/blob/f6ca0e397e1aec005ae49d5f88c829026d5af7d1/compiler/src/iree/compiler/Codegen/Dialect/GPU/Transforms/Passes.td#L57-L63
- However this is undesirable because then all transform passes will require every backend to be added as its dependency.

### Tasks

Upon discussion in discord, the conclusion is that following needs to be fixed:
1. Figure out why `registerAllDialects()` doesn't include the `amdgpu` dialect in `iree-opt` standalone pass invokation.
2. Figure out why `amdgpu` target isn't already included via `ROCMTarget` that registers `rocdl` dialect.
3. Fix dialect registration such that an arbitrary backend dependent pass can be invoked without having to manually add pass level dependencies
- An alternative is to provide `--register-dialect` as a plumbing for user to register dialect in passes especially in `Transforms` folder
- Note: The workaround specified in `4` is undesirable and is not considered as a proper fix to this ticket.

### Steps to reproduce your issue

1. Download [before_iree_gpu_lower_ops.txt](https://github.com/user-attachments/files/17683085/before_iree_gpu_lower_ops.txt)
the IR from print-after-all right before this pass happens
2. Use iree-opt to apply just this standalone pass via:
`iree-opt --iree-hal-target-backends=rocm --pass-pipeline="builtin.module(func.func(iree-gpu-lower-ops))" --iree-hip-target=gfx942 before_iree_gpu_lower_ops.mlir`
3. Observe the `iree-opt` crash when `iree-gpu-lower-ops` attempt to convert a `iree_gpu.multi_mma` op to `amdgpu.mfma` op.