Don't print the entire declaration of the alliassee when `->toChars()` is called on an `AliasDeclaration`; just printing the name will do. This fixes #305, which otherwise tries to generate {{{ class E { void A() { alias /* recurse into E->toCBuffer() */ m; } } }}} by way of an infinite recursion (causing a segfault when the stack runs out).

#ifndef LDC_IR_IRMODULE_H
#define LDC_IR_IRMODULE_H

#include "ir/ir.h"

struct Module;

struct IrModule : IrBase
{
    IrModule(Module* module, const char* srcfilename);
    virtual ~IrModule();

    Module* M;

    LLGlobalVariable* fileName;
    llvm::DICompileUnit diCompileUnit;
};

#endif