* Moved ir/irsymbol.cpp/h into ir/irdsymbol.cpp/h.

* Added #if IN_DMD versioning around DMD backend specific code in the D1 frontend, D2 is currently broken.
* All part of a greater cleanup scheme.

dmd/enum.h

@@ -65,8 +65,10 @@ struct EnumDeclaration : ScopeDsymbol
     void toDebug();
     int cvMember(unsigned char *p);
 
+#if IN_DMD
     Symbol *sinit;
     Symbol *toInitializer();
+#endif
 };