Claude review: misc: fastrpc: Move fdlist to invoke context structure

[Claude Code Review Bot <claude-review@example.com>]

Patch Review

**Assessment: Acceptable with minor comments**

This is a clean refactoring patch. Moving `fdlist` into `fastrpc_invoke_ctx` eliminates the redundant pointer computation in `fastrpc_put_args`.

One concern: In the original `fastrpc_put_args`, the fdlist pointer was computed using the actual scalar breakdown:

```c
fdlist = (uint64_t *)(pages + inbufs + outbufs + handles);
```

In `fastrpc_get_args`, it's now computed as:

```c
ctx->fdlist = (u64 *)(pages + ctx->nscalars);
```

Since `nscalars = inbufs + outbufs + REMOTE_SCALARS_INHANDLES(sc) + REMOTE_SCALARS_OUTHANDLES(sc)`, which equals `inbufs + outbufs + handles`, these are equivalent. This is correct.

The removal of the now-unused `outbufs`, `handles`, `list`, `pages` local variables from `fastrpc_put_args` is appropriate.

---
Generated by Claude Code Patch Reviewer