Fix win32 port to work with -Waddress (implement sys_*_valid_val() defines)

ports/win32/include/arch/sys_arch.h

@@ -37,7 +37,8 @@ struct _sys_sem {
   void *sem;
 };
 typedef struct _sys_sem sys_sem_t;
-#define sys_sem_valid(sema) (((sema) != NULL) && ((sema)->sem != NULL)  && ((sema)->sem != (void*)-1))
+#define sys_sem_valid_val(sema) (((sema).sem != NULL)  && ((sema).sem != (void*)-1))
+#define sys_sem_valid(sema) (((sema) != NULL) && sys_sem_valid_val(*(sema)))
 #define sys_sem_set_invalid(sema) ((sema)->sem = NULL)
 
 /* HANDLE is used for sys_mutex_t but we won't include windows.h */
@@ -45,7 +46,8 @@ struct _sys_mut {
   void *mut;
 };
 typedef struct _sys_mut sys_mutex_t;
-#define sys_mutex_valid(mutex) (((mutex) != NULL) && ((mutex)->mut != NULL)  && ((mutex)->mut != (void*)-1))
+#define sys_mutex_valid_val(mutex) (((mutex).mut != NULL)  && ((mutex).mut != (void*)-1))
+#define sys_mutex_valid(mutex) (((mutex) != NULL) && sys_mutex_valid_val(*(mutex)))
 #define sys_mutex_set_invalid(mutex) ((mutex)->mut = NULL)
 
 #ifndef MAX_QUEUE_ENTRIES
@@ -58,7 +60,8 @@ struct lwip_mbox {
 };
 typedef struct lwip_mbox sys_mbox_t;
 #define SYS_MBOX_NULL NULL
-#define sys_mbox_valid(mbox) ((mbox != NULL) && ((mbox)->sem != NULL)  && ((mbox)->sem != (void*)-1))
+#define sys_mbox_valid_val(mbox) (((mbox).sem != NULL)  && ((mbox).sem != (void*)-1))
+#define sys_mbox_valid(mbox) ((mbox != NULL) && sys_mbox_valid_val(*(mbox)))
 #define sys_mbox_set_invalid(mbox) ((mbox)->sem = NULL)
 
 /* DWORD (thread id) is used for sys_thread_t but we won't include windows.h */