Add a test triple to avoid failure under MS ABI.

MS ABI has slightly different rules for when destructors are implicitly
defined and when the 'delete this' is checked that are out of scope for
the intent of this test.

clang/test/CXX/special/class.dtor/p5-0x.cpp

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -verify -std=c++11 %s -Wno-defaulted-function-deleted
+// RUN: %clang_cc1 -verify -std=c++11 %s -Wno-defaulted-function-deleted -triple x86_64-linux-gnu
 
 struct NonTrivDtor {
   ~NonTrivDtor();