Remove grabbing __indirect_function_table

[tomaka]

This finishes to remove support for the sandboxing feature that no longer exists.

cc #170

[github-actions]

twiggy diff report

Difference in .wasm size before and after this pull request.

---

 Delta Bytes │ Item
─────────────┼──────────────────────────────────────────────────────────────────────────────────────────────────────
       -5008 ┊ smoldot::executor::vm::interpreter::InterpreterPrototype::new::h7a77c0ca2bf7d71d
       +4900 ┊ smoldot::executor::vm::interpreter::InterpreterPrototype::new::h9b9fc1dee63850cb
        -543 ┊ <&T as core::fmt::Display>::fmt::h17f9803b3a518e0f
        +483 ┊ <&T as core::fmt::Display>::fmt::h9320a5d074874245
        +393 ┊ smoldot::executor::vm::VirtualMachinePrototype::new::hcf3e75389d694152
        -341 ┊ <smoldot::executor::vm::NewErr as core::fmt::Debug>::fmt::h5018d442221ba759
        +317 ┊ <smoldot::executor::vm::NewErr as core::fmt::Debug>::fmt::hea17075d19ffe934
        -272 ┊ smoldot::executor::vm::VirtualMachinePrototype::new::h64cdb3a9d390fdea
        +225 ┊ smoldot::executor::host::HostVmPrototype::from_module::h8a849d3555d3c85b
        -128 ┊ data[0]
        +107 ┊ smoldot_light::sync_service::standalone::Task<TPlat>::process_foreground_message::hf08943ad3f61f7c8
        -107 ┊ wasmi::instance::Instance::get_table::h0579537588284faa
         -67 ┊ core::ptr::drop_in_place<smoldot::executor::vm::NewErr>::hd194a26f2ea93156
         +66 ┊ core::ptr::drop_in_place<smoldot::executor::vm::NewErr>::h6a998d81fac57e1a
         +59 ┊ <alloc::sync::Weak<T> as core::ops::drop::Drop>::drop::hf99f22a2f23445c6
         -49 ┊ smoldot::executor::vm::VirtualMachinePrototype::start::h3b116045171e805c
         -30 ┊ smoldot::executor::vm::VirtualMachine::into_prototype::h5a0c751165fb76b8
         +28 ┊ smoldot::sync::optimistic::OptimisticSync<TRq,TSrc,TBl>::new::h65f181de12c477f6
         +19 ┊ <core::future::from_generator::GenFuture<T> as core::future::future::Future>::poll::h3f708948b9a426ee
         -18 ┊ smoldot::executor::host::HostVmPrototype::run_vectored::h6b4397a78fb95559
        +109 ┊ ... and 25 more.
        +184 ┊ Σ [45 Total Rows]