[AArch64] Change int64_t from 'long long int' to 'long int' for AArch64 target.

Most 64-bit targets define int64_t as long int, and AArch64 should
make same definition to follow LP64 model. In GNU tool chain, int64_t
is defined as long int for 64-bit target. So to get consistent with GNU,
it's better Changing int64_t from 'long long int' to 'long int',
otherwise clang will get different name mangling suffix compared with g++.

llvm-svn: 202004
diff --git a/clang/lib/AST/ItaniumMangle.cpp b/clang/lib/AST/ItaniumMangle.cpp
index ca546d5..baa3e49 100644
--- a/clang/lib/AST/ItaniumMangle.cpp
+++ b/clang/lib/AST/ItaniumMangle.cpp
@@ -2203,7 +2203,7 @@
     return "Int16";
   case BuiltinType::Int:
     return "Int32";
-  case BuiltinType::LongLong:
+  case BuiltinType::Long:
     return "Int64";
   case BuiltinType::UChar:
     return "Uint8";
@@ -2211,7 +2211,7 @@
     return "Uint16";
   case BuiltinType::UInt:
     return "Uint32";
-  case BuiltinType::ULongLong:
+  case BuiltinType::ULong:
     return "Uint64";
   case BuiltinType::Half:
     return "Float16";
@@ -2246,7 +2246,7 @@
     case BuiltinType::UShort:
       EltName = "Poly16";
       break;
-    case BuiltinType::ULongLong:
+    case BuiltinType::ULong:
       EltName = "Poly64";
       break;
     default: