Create dex subdirectory

Move all the DexFile related source to a common subdirectory dex/ of
runtime.

Bug: 71361973
Test: make -j 50 test-art-host
Change-Id: I59e984ed660b93e0776556308be3d653722f5223
diff --git a/compiler/optimizing/stack_map_stream.cc b/compiler/optimizing/stack_map_stream.cc
index 4f43eb3..7010e3f 100644
--- a/compiler/optimizing/stack_map_stream.cc
+++ b/compiler/optimizing/stack_map_stream.cc
@@ -18,7 +18,7 @@
 
 #include "art_method-inl.h"
 #include "base/stl_util.h"
-#include "dex_file_types.h"
+#include "dex/dex_file_types.h"
 #include "optimizing/optimizing_compiler.h"
 #include "runtime.h"
 #include "scoped_thread_state_change-inl.h"