x64: Lower fcopysign, ceil, floor, nearest, and trunc in ISLE (#4730)

https://github.com/bytecodealliance/wasmtime/pull/4730

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

@@ -1770,7 +1770,8 @@ impl From<FloatCC> for FcmpImm {
 /// However the rounding immediate which this field helps make up, also includes
 /// bits 3 and 4 which define the rounding select and precision mask respectively.
 /// These two bits are not defined here and are implictly set to zero when encoded.
-pub(crate) enum RoundImm {
+#[derive(Clone, Copy)]
+pub enum RoundImm {
     RoundNearest = 0x00,
     RoundDown = 0x01,
     RoundUp = 0x02,