NFC: digital: Correct function name in the kerneldoc comments

Fix the following W=1 kernel build warning(s):

 net/nfc/digital_core.c:473: warning: expecting prototype for start_poll operation(). Prototype was for digital_start_poll() instead
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/nfc/digital_core.c

@@ -457,7 +457,7 @@ static void digital_add_poll_tech(struct nfc_digital_dev *ddev, u8 rf_tech,
 }
 
 /**
- * start_poll operation
+ * digital_start_poll - start_poll operation
  * @nfc_dev: device to be polled
  * @im_protocols: bitset of nfc initiator protocols to be used for polling
  * @tm_protocols: bitset of nfc transport protocols to be used for polling