MC/X86: Add stub AsmBackend.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96763 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86TargetMachine.cpp b/lib/Target/X86/X86TargetMachine.cpp
index 7802f98..56ddaf8 100644
--- a/lib/Target/X86/X86TargetMachine.cpp
+++ b/lib/Target/X86/X86TargetMachine.cpp
@@ -51,6 +51,12 @@
                                       createX86_32MCCodeEmitter);
   TargetRegistry::RegisterCodeEmitter(TheX86_64Target,
                                       createX86_64MCCodeEmitter);
+
+  // Register the asm backend.
+  TargetRegistry::RegisterAsmBackend(TheX86_32Target,
+                                     createX86_32AsmBackend);
+  TargetRegistry::RegisterAsmBackend(TheX86_64Target,
+                                     createX86_64AsmBackend);
 }