[AArch64] Change the preferred alignment for char and short.

This reinstates commits r273280 and r273289.

Original Review: http://reviews.llvm.org/D21414.

llvm-svn: 274791
diff --git a/clang/lib/Basic/Targets.cpp b/clang/lib/Basic/Targets.cpp
index a8158a2..80b44fc 100644
--- a/clang/lib/Basic/Targets.cpp
+++ b/clang/lib/Basic/Targets.cpp
@@ -5994,7 +5994,7 @@
     if (getTriple().isOSBinFormatMachO())
       resetDataLayout("e-m:o-i64:64-i128:128-n32:64-S128");
     else
-      resetDataLayout("e-m:e-i64:64-i128:128-n32:64-S128");
+      resetDataLayout("e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128");
   }
 
 public:
@@ -6012,7 +6012,7 @@
 class AArch64beTargetInfo : public AArch64TargetInfo {
   void setDataLayout() override {
     assert(!getTriple().isOSBinFormatMachO());
-    resetDataLayout("E-m:e-i64:64-i128:128-n32:64-S128");
+    resetDataLayout("E-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128");
   }
 
 public: