[weak vtables] Remove a bunch of weak vtables

This patch removes most of the trivial cases of weak vtables by pinning them to
a single object file. The memory leaks in this version have been fixed. Thanks
Alexey for pointing them out.

Differential Revision: http://llvm-reviews.chandlerc.com/D2068

Reviewed by Andy

llvm-svn: 195064
diff --git a/llvm/lib/Target/SystemZ/SystemZMachineFunctionInfo.h b/llvm/lib/Target/SystemZ/SystemZMachineFunctionInfo.h
index 69c2691..845291f 100644
--- a/llvm/lib/Target/SystemZ/SystemZMachineFunctionInfo.h
+++ b/llvm/lib/Target/SystemZ/SystemZMachineFunctionInfo.h
@@ -15,6 +15,7 @@
 namespace llvm {
 
 class SystemZMachineFunctionInfo : public MachineFunctionInfo {
+  virtual void anchor();
   unsigned LowSavedGPR;
   unsigned HighSavedGPR;
   unsigned VarArgsFirstGPR;