rtos: fix style in rtos wait

Found during editing copyright message

Author: 0xc0170

platform/mbed_wait_api_rtos.cpp

@@ -54,7 +54,7 @@ void wait_ms(int ms)
     if (core_util_is_isr_active() || !core_util_are_interrupts_enabled()) {
 #if defined(MBED_TRAP_ERRORS_ENABLED) && MBED_TRAP_ERRORS_ENABLED
         MBED_ERROR(MBED_MAKE_ERROR(MBED_MODULE_PLATFORM, MBED_ERROR_INVALID_OPERATION),
-                    "Deprecated behavior: milli-sec delay should not be used in interrupt.\n");
+                   "Deprecated behavior: milli-sec delay should not be used in interrupt.\n");
 #else
         wait_us(ms * 1000);
 #endif