IR: include a fence in CPUID

easier for post-RA to chew thru.

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>

FEXCore/Source/Interface/Core/OpcodeDispatcher.cpp

@@ -1311,7 +1311,6 @@ void OpDispatchBuilder::CPUIDOp(OpcodeArgs) {
   Ref RCX = _AllocateGPR(false);
   Ref RDX = _AllocateGPR(false);
 
-  _Fence({FEXCore::IR::Fence_Inst});
   _CPUID(Src, Leaf, RAX, RBX, RCX, RDX);
 
   StoreGPRRegister(X86State::REG_RAX, RAX);