Audio V4: Duplicate V2 tests

Because VTS must no be modified for old API version (except bug fixes),
as that could break retrocompatiblity.
As a result, a full copy is made. This commit is only:
$ cp -r core/2.0/vts/ core/4.0/vts
$ cp -r effect/2.0/vts/ effect/4.0/vts

With a V2 replaced by V4 test target name to avoid conflict.

Bug: 38184704
Test: Compile
Change-Id: Iddf9e7a9d42bfe84cf067a08d249a9cc0e6b7241
Signed-off-by: Kevin Rocard <krocard@google.com>