Cranelift: load.f32x2 unimplemented on x86_64

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### `.clif` Test Case

```
function u0:0(f32x2) -> f32x2 system_v {
ss0 = explicit_slot 16
ss1 = explicit_slot 16
sig0 = (f32) -> f32 system_v
fn0 = u0:1 sig0 ; "cosf"

block0(v0: f32x2):
stack_store v0, ss1

; _0 = simd_fcos::(move _1)
v1 = stack_load.f32 ss1
v2 = call fn0(v1) ; lib_call cosf
stack_store v2, ss0
v3 = stack_load.f32 ss1+4
v4 = call fn0(v3) ; lib_call cosf
stack_store v4, ss0+4

v5 = stack_load.f32x2 ss0
return v5
}
```

### Steps to Reproduce

* Compile on x86_64

### Expected Results

Compiles

### Actual Results

```
thread '' panicked at /home/bjorn/.cargo/registry/src/index.crates.io-6f17d22bba15001f/cranelift-codegen-0.105.2/src/machinst/lower.rs:766:21:
should be implemented in ISLE: inst = `v5 = load.f32x2 notrap v11`, type = `Some(types::F32X2)`
stack backtrace:
0: rust_begin_unwind
at /rustc/46b180ec2452d388c5d9c14009442e2e0beb01d7/library/std/src/panicking.rs:645:5
1: core::panicking::panic_fmt
at /rustc/46b180ec2452d388c5d9c14009442e2e0beb01d7/library/core/src/panicking.rs:72:14
2: cranelift_codegen::machinst::compile::compile
3: ::compile_function
4: cranelift_codegen::context::Context::compile_stencil
5: cranelift_codegen::context::Context::compile_and_emit
6: ::define_function_with_control_plane
7: cranelift_module::module::Module::define_function
8: rustc_codegen_cranelift::base::compile_fn
```

### Versions and Environment

Cranelift version or commit: Cranelift 1.105.2

Operating system: N/A

Architecture: x86_64

### Extra Info

Anything else you'd like to add?