Turn off dump/emit routines when building minimal subzero.

src/IceGlobalContext.h

Index: src/IceGlobalContext.h
diff --git a/src/IceGlobalContext.h b/src/IceGlobalContext.h
index bdc461e65867740b2a937ea22f2231166300f080..43f65ad8fe8a747cfddb85b2a0dd7faac3f59e18 100644
--- a/src/IceGlobalContext.h
+++ b/src/IceGlobalContext.h
@@ -48,6 +48,8 @@ public:
   void updateSpills() { ++Spills; }
   void updateFills() { ++Fills; }
   void dump(const IceString &Name, Ostream &Str) {
+    if (!ALLOW_DUMP)
+      return;
     Str << "|" << Name << "|Inst Count  |" << InstructionsEmitted << "\n";
     Str << "|" << Name << "|Regs Saved  |" << RegistersSaved << "\n";
     Str << "|" << Name << "|Frame Bytes |" << FrameBytes << "\n";