Core: Change the type of ns_caller from int32_t to bool

Change the ns_caller in tfm_spm_check_authorization from int32_t
to bool to better indicate the meaning.

Change-Id: Iaa1d23fe439c4952e556f6c38b4db2c30d11cbbe
Signed-off-by: Summer Qin <summer.qin@arm.com>
diff --git a/secure_fw/spm/spm_api_ipc.c b/secure_fw/spm/spm_api_ipc.c
index 1ea52e7..a8b6c14 100644
--- a/secure_fw/spm/spm_api_ipc.c
+++ b/secure_fw/spm/spm_api_ipc.c
@@ -264,7 +264,7 @@
 
 int32_t tfm_spm_check_authorization(uint32_t sid,
                                     struct tfm_spm_service_t *service,
-                                    int32_t ns_caller)
+                                    bool ns_caller)
 {
     struct spm_partition_desc_t *partition = NULL;
     int32_t i;