Initialize the address-significance table fragment's layout order.

This fragment is created after layout, which is where the order
normally gets set.

Should fix a test failure under msan.

llvm-svn: 340516

lib/MC/WinCOFFObjectWriter.cpp

@@ -1036,6 +1036,7 @@ uint64_t WinCOFFObjectWriter::writeObject(MCAssembler &Asm,
   // Create the contents of the .llvm_addrsig section.
   if (EmitAddrsigSection) {
     auto Frag = new MCDataFragment(AddrsigSection);
+    Frag->setLayoutOrder(0);
     raw_svector_ostream OS(Frag->getContents());
     for (const MCSymbol *S : AddrsigSyms) {
       if (!S->isTemporary()) {