Build: Minor refine for build configurations

The patch includes 3 refines:
1. Removes deprecated TFM_LEGACY_API config

2. CORE_TEST_POSITIVE tests can be enabled only in TFM isolation
   level 1. The check is currently done in the non_secure_suites.c.
   This patch moves the check from source file to CMake file to
   align with the other test suites.

3. Removes extra #if check for audit log test suite in source code.
   The check has been done in CMake

Change-Id: I1b28f5f5139a0ff762f73334aadd38a931440b29
Signed-off-by: Kevin Peng <kevin.peng@arm.com>
3 files changed