mbed boot: fix IAR mbed_main

We do not use __iar_argc_argv() anymore. Invoke mbed_main right before main in pre_main
function. This fixes the test call_before_main.

Author: 0xc0170

rtos/mbed_boot.c

@@ -520,6 +520,7 @@ void pre_main(void)
     if (low_level_init_needed) {
         __iar_dynamic_initialization();
     }
+    mbed_main();
     main();
 }
 
@@ -547,16 +548,6 @@ void __iar_program_start( void )
   mbed_start_main();
 }
 
-/* IAR doesn't have the $Super/$Sub mechanism of armcc, nor something equivalent
- * to ld's --wrap. It does have a --redirect, but that doesn't help, since redirecting
- * 'main' to another symbol looses the original 'main' symbol. However, its startup
- * code will call a function to setup argc and argv (__iar_argc_argv) if it is defined.
- * Since mbed doesn't use argc/argv, we use this function to call our mbed_main.
- */
-void __iar_argc_argv() {
-    mbed_main();
-}
-
 /* Thread safety */
 static osMutexId_t std_mutex_id_sys[_MAX_LOCK] = {0};
 static os_mutex_t  std_mutex_sys[_MAX_LOCK] = {0};