Put the PR16167 tests together

llvm-svn: 183046
diff --git a/clang/test/SemaCXX/linkage-spec.cpp b/clang/test/SemaCXX/linkage-spec.cpp
index 7681c7d..fc14081 100644
--- a/clang/test/SemaCXX/linkage-spec.cpp
+++ b/clang/test/SemaCXX/linkage-spec.cpp
@@ -116,3 +116,4 @@
 }
 
 extern "C" void PR16167; // expected-error {{variable has incomplete type 'void'}}
+extern void PR16167_0; // expected-error {{variable has incomplete type 'void'}}