WebAssembly: MCAsmInfo only has one syntax variant for now.

[jfb]

Summary

MCAsmInfo is set up with the default AssemblerDialect, which is zero.

llvm/trunk/lib/Target/WebAssembly/MCTargetDesc/WebAssemblyMCTargetDesc.cpp

 #define GET_SUBTARGETINFO_MC_DESC
 #include "WebAssemblyGenSubtargetInfo.inc"
 
 #define GET_REGINFO_MC_DESC
 #include "WebAssemblyGenRegisterInfo.inc"
 
 static MCAsmInfo *createWebAssemblyMCAsmInfo(const MCRegisterInfo &MRI,
                                              const Triple &TT) {
-  MCAsmInfo *MAI = new WebAssemblyMCAsmInfo(TT);
-  return MAI;
+  return new WebAssemblyMCAsmInfo(TT);
 }
 
 static MCInstPrinter *
 createWebAssemblyMCInstPrinter(const Triple &T, unsigned SyntaxVariant,
                                const MCAsmInfo &MAI, const MCInstrInfo &MII,
                                const MCRegisterInfo &MRI) {
-  if (SyntaxVariant == 0 || SyntaxVariant == 1)
-    return new WebAssemblyInstPrinter(MAI, MII, MRI);
-  return nullptr;
+  assert(SyntaxVariant == 0);
 }
 
 // Force static initialization.
 extern "C" void LLVMInitializeWebAssemblyTargetMC() {
   for (Target *T : {&TheWebAssemblyTarget32, &TheWebAssemblyTarget64}) {
     // Register the MC asm info.
     RegisterMCAsmInfoFn X(*T, createWebAssemblyMCAsmInfo);
 
     // Register the MCInstPrinter.
     TargetRegistry::RegisterMCInstPrinter(*T, createWebAssemblyMCInstPrinter);
   }
 }