CKM: Update old initial values tests

CKM: Update old initial values tests

With introduction of support for initial values (including encrypted
ones) in key manager's TZ backend the xml scheme and the encryption
scheme has been changed. Also the SW backend does not handle encrypted
initial values. As a result the existing tests for initial values
started to fail.

To make them work again the following changes are introduced:
- Use version 2 in test xml files.
- Remove all code, files and xml elements related to encrypted initial
  values from old tests (T6001-T6999).
- Enable old initial values tests in an environment with no TZ support.
- Add a TODO list for initial values tests.

Change-Id: I1f9cb80b6080f628e2058c9165dfd424b0ad44d1