Don't reuse registers in the x64 div lowering (#5356)

Introduce a temporary for an intermediate value in the lowering of div in the x64 backend. Additionally, add a src argument to the shift_r smart constructor, which is why the diff got larger than just the div lowering.

cranelift/codegen/src/isa/x64/inst/emit.rs

@@ -2344,6 +2344,7 @@ pub(crate) fn emit(
                 OperandSize::Size64,
                 ShiftKind::ShiftRightLogical,
                 Imm8Gpr::new(Imm8Reg::Imm8 { imm: 1 }).unwrap(),
+                tmp_gpr1,
                 Writable::from_reg(tmp_gpr1),
             );
             inst.emit(&[], sink, info, state);