PPC[liftoff]: Don't cast Double to FP after copysign

Executing a frsp after copysign changes any SNaN inputs
to QNaN which causes test failures.

Change-Id: Ieab5d24fd09344e0a3108565f478fda3b5889556
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3576793Reviewed-by: Junliang Yan <junyan@redhat.com>
Commit-Queue: Milad Farazmand <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/main@{#79866}

src/wasm/baseline/ppc/liftoff-assembler-ppc.h

@@ -1142,7 +1142,7 @@ UNOP_LIST(EMIT_UNOP_FUNCTION)
 // return_val, return_type)
 #define BINOP_LIST(V)                                                          \
   V(f32_copysign, CopySignF64, DoubleRegister, DoubleRegister, DoubleRegister, \
-    , , , ROUND_F64_TO_F32, , void)                                            \
+    , , , USE, , void)                                                         \
   V(f64_copysign, CopySignF64, DoubleRegister, DoubleRegister, DoubleRegister, \
     , , , USE, , void)                                                         \
   V(f32_min, MinF64, DoubleRegister, DoubleRegister, DoubleRegister, , , ,     \