Pass the Mangler by reference.

It is never null and it is not used in casts, so there is no reason to use a
pointer. This matches how we pass TM.

llvm-svn: 201025
diff --git a/llvm/lib/Target/PowerPC/PPCTargetObjectFile.h b/llvm/lib/Target/PowerPC/PPCTargetObjectFile.h
index 8042a79..475ebd8 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetObjectFile.h
+++ b/llvm/lib/Target/PowerPC/PPCTargetObjectFile.h
@@ -23,7 +23,7 @@
     void Initialize(MCContext &Ctx, const TargetMachine &TM) LLVM_OVERRIDE;
 
     const MCSection *SelectSectionForGlobal(const GlobalValue *GV,
-                                            SectionKind Kind, Mangler *Mang,
+                                            SectionKind Kind, Mangler &Mang,
                                             const TargetMachine &TM) const
         LLVM_OVERRIDE;