Cranelift: Incorrect abi for i128, i128 return value on x86_64 sysv

### Expected Results

All return values are returned using a single return pointer.

### Actual Results

Return values are put into registers where possible and on the stack for the rest.

### Versions and Environment

Cranelift version or commit: 0.111

Operating system: Linux

Architecture: x86_64

### Extra Info

This is one of the causes for https://github.com/rust-lang/rustc_codegen_cranelift/issues/1525. The same issue may exist on aarch64 and other archs too, but haven't checked yet.