Cranelift: Panic on `aarch64` backend with large offset `stack_store`

👋 Hey,

Fuzzgen found this when I tried to increase the max stack slot size.

### `.clif` Test Case

```
test compile
target aarch64

function u1:0() system_v {
ss0 = explicit_slot 5459

block0:
v25 = iconst.i32 0
stack_store v25, ss0+4095 ; v25 = 0
return
}
```

### Steps to Reproduce

* `clif-util compile --target aarch64 -D ./the-above.clif`

### Expected Results

The function to compile

### Actual Results

```
Running `/home/afonso/git/wasmtime/target/debug/clif-util compile --target aarch64 -D ./lmao.clif`
thread 'main' panicked at 'assertion failed: `(left != right)`
left: `p63i`,
right: `p63i`', cranelift/codegen/src/isa/aarch64/inst/emit.rs:767:17
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
```

### Versions and Environment

Cranelift version or commit: 4fc768df36e53d1c9f42db6b3ea52af45a3dc129 (current main)

Operating system: Linux

Architecture: AArch64

Start by running the provided `clif-util compile --target aarch64 -D` reproducer, then inspect the assertion at `cranelift/codegen/src/isa/aarch64/inst/emit.rs:767`. Done means the `.clif` test case compiles for the aarch64 target without panicking.

Written by the indexing model from the issue text.