Get rid of test_finish macro and related ATF cruft (#633)

Closes #431

Signed-off-by: Kevin Petit <kevin.petit@arm.com>

test_conformance/allocations/allocation_functions.cpp

@@ -275,7 +275,6 @@ int allocate_size(cl_context context, cl_command_queue *queue, cl_device_id devi
     // Otherwise we succeeded
     if (result != SUCCEEDED) {
       log_error("Test logic error.");
-      test_finish();
       exit(-1);
     }
     amount_allocated += allocation_this_time;

test_conformance/allocations/main.cpp

@@ -277,7 +277,6 @@ int main(int argc, const char *argv[])
     argc = parseCustomParam(argc, argv);
     if (argc == -1)
     {
-        test_finish();
         return 1;
     }