add support for hidden visibility to darwin/ppc and linux/ppc targets

llvm-svn: 33200
diff --git a/llvm/lib/Target/PowerPC/PPCTargetAsmInfo.cpp b/llvm/lib/Target/PowerPC/PPCTargetAsmInfo.cpp
index 3def031..6045cfa 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetAsmInfo.cpp
+++ b/llvm/lib/Target/PowerPC/PPCTargetAsmInfo.cpp
@@ -55,6 +55,7 @@
   StaticDtorsSection = ".mod_term_func";
   UsedDirective = "\t.no_dead_strip\t";
   WeakRefDirective = "\t.weak_reference\t";
+  HiddenDirective = "\t.private_extern\t";
 }
 
 LinuxTargetAsmInfo::LinuxTargetAsmInfo(const PPCTargetMachine &TM)