Revert cdex version back to 001.

We bumped the version due to disabling deduping but:
1) the reason for disabing deduping are minor (access checks in Java)
2) public users (and dogfooders now) will have already regenerate a cdex
   file with code item deduping removed, thanks to the vdex format having
   changed in S.

Bug: 192327398
Test: test.py
Change-Id: I5ccb2dbc37daa682909db671f400f151152f70ac
Merged-In: I5ccb2dbc37daa682909db671f400f151152f70ac
(cherry picked from commit 45848daf541599548145c265ece14aad0e973639)
diff --git a/libdexfile/dex/compact_dex_file.h b/libdexfile/dex/compact_dex_file.h
index 9a12f4a..9c3b7a4 100644
--- a/libdexfile/dex/compact_dex_file.h
+++ b/libdexfile/dex/compact_dex_file.h
@@ -28,7 +28,7 @@
  public:
   static constexpr uint8_t kDexMagic[kDexMagicSize] = { 'c', 'd', 'e', 'x' };
   // Last change: remove code item deduping.
-  static constexpr uint8_t kDexMagicVersion[] = {'0', '0', '2', '\0'};
+  static constexpr uint8_t kDexMagicVersion[] = {'0', '0', '1', '\0'};
 
   enum class FeatureFlags : uint32_t {
     kDefaultMethods = 0x1,