Replace string GNU Triples with llvm::Triple in MCSubtargetInfo and create*MCSubtargetInfo(). NFC.

Summary:
This continues the patch series to eliminate StringRef forms of GNU triples
from the internals of LLVM that began in r239036.

Reviewers: rafael

Reviewed By: rafael

Subscribers: rafael, ted, jfb, llvm-commits, rengolin, jholewinski

Differential Revision: http://reviews.llvm.org/D10311

llvm-svn: 239467
diff --git a/llvm/lib/Target/SystemZ/SystemZTargetMachine.cpp b/llvm/lib/Target/SystemZ/SystemZTargetMachine.cpp
index a34cdaf..8de050a 100644
--- a/llvm/lib/Target/SystemZ/SystemZTargetMachine.cpp
+++ b/llvm/lib/Target/SystemZ/SystemZTargetMachine.cpp
@@ -84,10 +84,10 @@
                                            const TargetOptions &Options,
                                            Reloc::Model RM, CodeModel::Model CM,
                                            CodeGenOpt::Level OL)
-    : LLVMTargetMachine(T, computeDataLayout(TT, CPU, FS),
-                        TT, CPU, FS, Options, RM, CM, OL),
+    : LLVMTargetMachine(T, computeDataLayout(TT, CPU, FS), TT, CPU, FS, Options,
+                        RM, CM, OL),
       TLOF(make_unique<TargetLoweringObjectFileELF>()),
-      Subtarget(TT, CPU, FS, *this) {
+      Subtarget(Triple(TT), CPU, FS, *this) {
   initAsmInfo();
 }