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/PowerPC/PPCSubtarget.h b/llvm/lib/Target/PowerPC/PPCSubtarget.h
index 8d95508..e8abe00 100644
--- a/llvm/lib/Target/PowerPC/PPCSubtarget.h
+++ b/llvm/lib/Target/PowerPC/PPCSubtarget.h
@@ -135,8 +135,8 @@
   /// This constructor initializes the data members to match that
   /// of the specified triple.
   ///
-  PPCSubtarget(const std::string &TT, const std::string &CPU,
-               const std::string &FS, const PPCTargetMachine &TM);
+  PPCSubtarget(const Triple &TT, const std::string &CPU, const std::string &FS,
+               const PPCTargetMachine &TM);
 
   /// ParseSubtargetFeatures - Parses features string setting specified
   /// subtarget options.  Definition of function is auto generated by tblgen.