Fix a bug that would cause subzero to fail when --threads=0.

Creates a single TargetDataLowering.

BUG= None
R=stichnot@chromium.org

Review URL: https://codereview.chromium.org/1179313004.

src/IceTargetLoweringARM32.cpp

diff --git a/src/IceTargetLoweringARM32.cpp b/src/IceTargetLoweringARM32.cpp
index 2d3c5c1..9bb2386 100644
--- a/src/IceTargetLoweringARM32.cpp
+++ b/src/IceTargetLoweringARM32.cpp
@@ -2207,20 +2207,20 @@
 TargetDataARM32::TargetDataARM32(GlobalContext *Ctx)
     : TargetDataLowering(Ctx) {}
 
-void TargetDataARM32::lowerGlobals(
-    std::unique_ptr<VariableDeclarationList> Vars) {
+void TargetDataARM32::lowerGlobals(const VariableDeclarationList &Vars,
+                                   const IceString &SectionSuffix) {
   switch (Ctx->getFlags().getOutFileType()) {
   case FT_Elf: {
     ELFObjectWriter *Writer = Ctx->getObjectWriter();
-    Writer->writeDataSection(*Vars, llvm::ELF::R_ARM_ABS32);
+    Writer->writeDataSection(Vars, llvm::ELF::R_ARM_ABS32, SectionSuffix);
   } break;
   case FT_Asm:
   case FT_Iasm: {
     const IceString &TranslateOnly = Ctx->getFlags().getTranslateOnly();
     OstreamLocker L(Ctx);
-    for (const VariableDeclaration *Var : *Vars) {
+    for (const VariableDeclaration *Var : Vars) {
       if (GlobalContext::matchSymbolName(Var->getName(), TranslateOnly)) {
-        emitGlobal(*Var);
+        emitGlobal(*Var, SectionSuffix);
       }
     }
   } break;