Update makefiles for CAS.

Now that we can generate regular HIDL HAL makefiles
which frameworks.jar can link against, do this for
media cas.

Test: run cts-dev --module CtsMediaTestCases
  --test android.media.cts.MediaCasTest
=>
 Invocation finished in 27s. PASSED: 6, FAILED: 0, MODULES: 1 of 1
Bug: 64294630
Change-Id: I40d9096bd2fa18ec420e1ca5124b92e42d4a68ca