change `InlineAsmCtxt` to not talk about `FnCtxt`
wip for https://github.com/rust-lang/compiler-team/issues/529. this currently uses both the `FnCtxt` and is used by `check_mod_item_types`. This should be the only thing blocking that MCP afaict.
I am still unsure whether `rustc_hir_typeck` should depend on `rustc_hir_analysis` to use the `InlineAsmCtxt`. I think that's the best solution for now, so that's what I will go for
r? `@compiler-errors`