SPM: Sort out tfm_secure_api.c file

- Rename 'tfm_utils.h' to 'utilities.h'.
- Rename 'tfm_spm_services_api.h'to 'tfm_spm_services.h'.
- Move 'tfm_secure_api.c' from spm/runtime to spm/model_func and
  sort out the content

Change-Id: Ie8831e2b1430eab6a2edc9b6c0487ef14f2fafc6
Signed-off-by: Summer Qin <summer.qin@arm.com>
diff --git a/secure_fw/spm/model_ipc/tfm_thread.c b/secure_fw/spm/model_ipc/tfm_thread.c
index 74af5a9..e3554e3 100644
--- a/secure_fw/spm/model_ipc/tfm_thread.c
+++ b/secure_fw/spm/model_ipc/tfm_thread.c
@@ -7,7 +7,7 @@
 #include <inttypes.h>
 #include "tfm_arch.h"
 #include "tfm_thread.h"
-#include "tfm_utils.h"
+#include "utilities.h"
 #include "tfm_memory_utils.h"
 #include "tfm/tfm_core_svc.h"
 #include "spm_api.h"