Change '@SECREL' suffix to GAS-compatible '@SECREL32'.

'@SECREL' is what is used by the Microsoft assembler, but GNU as expects '@SECREL32'.
With the patch, the MC-generated code works fine in combination with a recent GNU as (2.23.51.20120920 here).

Patch by David Nadlinger!
Differential Revision: http://llvm-reviews.chandlerc.com/D429

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178427 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86AsmPrinter.cpp b/lib/Target/X86/X86AsmPrinter.cpp
index ac5daec..6b228b0 100644
--- a/lib/Target/X86/X86AsmPrinter.cpp
+++ b/lib/Target/X86/X86AsmPrinter.cpp
@@ -201,7 +201,7 @@
   case X86II::MO_TLVP_PIC_BASE:
     O << "@TLVP" << '-' << *MF->getPICBaseSymbol();
     break;
-  case X86II::MO_SECREL:      O << "@SECREL";      break;
+  case X86II::MO_SECREL:    O << "@SECREL32";  break;
   }
 }