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_rpc.c b/secure_fw/spm/model_ipc/tfm_rpc.c
index f2778aa..351c971 100644
--- a/secure_fw/spm/model_ipc/tfm_rpc.c
+++ b/secure_fw/spm/model_ipc/tfm_rpc.c
@@ -8,7 +8,7 @@
 #include "spm_api.h"
 #include "spm_psa_client_call.h"
 #include "tfm_rpc.h"
-#include "tfm_utils.h"
+#include "utilities.h"
 
 static void default_handle_req(void)
 {