SST: Rename prepare and wipe interface names

This patch renames filenames and interface names to have a more
consistent names. It also updates the dependant tests.

The changes are:
 - sst_core_interface files to sst_object_system
 - sst_object_prepare interface to sst_system_prepare
 - sst_object_wipe_all interface to sst_system_wipe_all
 - asset to object
 - add missing platform/ext/driver directory in cmake

Change-Id: I975d60e6ececec05373bcf94d7bc2ddfe03ac7f6
Signed-off-by: Marc Moreno <marc.morenoberengue@arm.com>
diff --git a/test/framework/secure_suites.c b/test/framework/secure_suites.c
index 144cfef..f002cd7 100644
--- a/test/framework/secure_suites.c
+++ b/test/framework/secure_suites.c
@@ -13,7 +13,7 @@
 #include "test/suites/sst/secure/sst_tests.h"
 #include "test/suites/log/secure/log_s_tests.h"
 #include "test/suites/invert/secure/invert_s_tests.h"
-#include "secure_fw/services/secure_storage/sst_core_interface.h"
+#include "secure_fw/services/secure_storage/sst_object_system.h"
 
 static struct test_suite_t test_suites[] = {
 #ifdef SERVICES_TEST_S
@@ -42,8 +42,8 @@
 static void tear_down_integ_test(void)
 {
     /* Leave the SST area clean after execute the tests */
-    sst_object_wipe_all();
-    sst_object_prepare();
+    sst_system_wipe_all();
+    sst_system_prepare();
 }
 
 void start_integ_test(void)