remove the unnecessary variable.

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@1630 bbd45198-f89e-11dd-88c7-29a3b14d5316

bsp/lpc2478/startup.c

@@ -94,15 +94,13 @@ void rtthread_startup(void)
 	
 	/* never reach here */
 	return ;
-}
-
+}
+
 #ifdef __CC_ARM
 int main(void)
-{
-	rt_uint32_t UNUSED level;
-
+{
 	/* disable interrupt first */
-	level = rt_hw_interrupt_disable();
+	rt_hw_interrupt_disable();
 
 	/* invoke rtthread_startup */
 	rtthread_startup();