input: Unspecified device as /devices/virtual/input/inputx問題解決

1.將input子系統中的handler層和core層對應的代碼編譯進內核鏡像中:zImage
	make menuconfig
		Device Drivers  ---> 
					|	//核心層：drivers/input/input.c
			 Input device support  --->
			     			|	//數據處理層：drivers/input/evdev.c
				 	<*>   Event interface 
2.在創建一個input_dev對象後
	static struct input_dev *button_dev;
	button_dev = input_allocate_device();  
	//對該對象下的name成員添加描述信息
	buttons_dev->name = "button_dev";