[lwIP] fix lwip sem/mutex valid issue.

components/net/lwip/port/sys_arch.c

@@ -208,7 +208,11 @@ u32_t sys_arch_sem_wait(sys_sem_t *sem, u32_t timeout)
  */
 int sys_sem_valid(sys_sem_t *sem)
 {
-    return (int)(*sem);
+    int ret = 0;
+
+    if (*sem) ret = 1;
+
+    return ret;
 }
 #endif
 
@@ -283,7 +287,11 @@ void sys_mutex_free(sys_mutex_t *mutex)
  */
 int sys_mutex_valid(sys_mutex_t *mutex)
 {
-    return (int)(*mutex);
+    int ret = 0;
+
+    if (*mutex) ret = 1;
+
+    return ret;
 }
 #endif
 
@@ -458,7 +466,11 @@ u32_t sys_arch_mbox_tryfetch(sys_mbox_t *mbox, void **msg)
  */
 int sys_mbox_valid(sys_mbox_t *mbox)
 {
-    return (int)(*mbox);
+    int ret = 0;
+
+    if (*mbox) ret = 1;
+
+    return ret;
 }
 #endif