Implement initial-exec TLS model for 32-bit PIC x86

This fixes a TODO from 2007 :) Previously, LLVM would emit the wrong
code here (see the update to test/CodeGen/X86/tls-pie.ll).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156611 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86AsmPrinter.cpp b/lib/Target/X86/X86AsmPrinter.cpp
index 7db7ccb..6d97f46 100644
--- a/lib/Target/X86/X86AsmPrinter.cpp
+++ b/lib/Target/X86/X86AsmPrinter.cpp
@@ -190,6 +190,7 @@
   case X86II::MO_INDNTPOFF: O << "@INDNTPOFF"; break;
   case X86II::MO_TPOFF:     O << "@TPOFF";     break;
   case X86II::MO_NTPOFF:    O << "@NTPOFF";    break;
+  case X86II::MO_GOTNTPOFF: O << "@GOTNTPOFF"; break;
   case X86II::MO_GOTPCREL:  O << "@GOTPCREL";  break;
   case X86II::MO_GOT:       O << "@GOT";       break;
   case X86II::MO_GOTOFF:    O << "@GOTOFF";    break;