Debug info - generalize namespace test to not depend on a DW_TAG_file_type entry

This isn't necessary & with the next change to LLVM the DW_TAG_file_type entry
won't be emitted at all - only the raw filename/directory pair, so match on
that directly instead.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177609 91177308-0d34-0410-b5e6-96231b3b80d8

test/CodeGenCXX/debug-info-namespace.cpp

@@ -7,8 +7,8 @@ int i;
 }
 }
 
-// CHECK: [[FILE:![0-9]*]]} ; [ DW_TAG_file_type ] [{{.*}}/test/CodeGenCXX/debug-info-namespace.cpp]
+// CHECK: [[FILE:![0-9]*]] {{.*}}debug-info-namespace.cpp"
 // CHECK: [[VAR:![0-9]*]] = {{.*}}, metadata [[NS:![0-9]*]], metadata !"i", {{.*}} ; [ DW_TAG_variable ] [i]
 // CHECK: [[NS]] = {{.*}}, metadata [[FILE2:![0-9]*]], metadata [[CTXT:![0-9]*]], {{.*}} ; [ DW_TAG_namespace ] [B] [line 1]
-// CHECK: [[CTXT]] = {{.*}}, metadata [[FILE:![0-9]*]], null, {{.*}} ; [ DW_TAG_namespace ] [A] [line 3]
+// CHECK: [[CTXT]] = {{.*}}, metadata [[FILE]], null, {{.*}} ; [ DW_TAG_namespace ] [A] [line 3]
 // CHECK: [[FILE2]]} ; [ DW_TAG_file_type ] [{{.*}}foo.cpp]