[kernel] enable RT_DEBUG_DEVICE by default and move weak rt_hw_dealy_us in kservice.c

src/kservice.c

@@ -45,6 +45,13 @@ static volatile int __rt_errno;
 static rt_device_t _console_device = RT_NULL;
 #endif
 
+RT_WEAK void rt_hw_us_delay(rt_uint32_t us)
+{
+    (void) us;
+    RT_DEBUG_LOG(RT_DEBUG_DEVICE, ("rt_hw_us_delay() doesn't support for this board."
+        "Please consider implementing rt_hw_us_delay() in another file."));
+}
+
 /**
  * This function gets the global errno for the current thread.
  *