PPC: Clear VXCVI before DoubleToInt64 conversion

Change-Id: Ic5d52b3a7be345cfc4f104f83f23a4deb5972e4f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2545622Reviewed-by: Junliang Yan <junyan@redhat.com>
Reviewed-by: Milad Fa <mfarazma@redhat.com>
Commit-Queue: Milad Fa <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/master@{#71243}

src/compiler/backend/ppc/code-generator-ppc.cc

@@ -1918,9 +1918,7 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
 #if V8_TARGET_ARCH_PPC64
       bool check_conversion =
           (opcode == kPPC_DoubleToInt64 && i.OutputCount() > 1);
-      if (check_conversion) {
         __ mtfsb0(VXCVI);  // clear FPSCR:VXCVI bit
-      }
 #endif
       __ ConvertDoubleToInt64(i.InputDoubleRegister(0),
 #if !V8_TARGET_ARCH_PPC64