NFC: Add dev_up and dev_down control operations

Add 2 new nfc control operations:
dev_up to turn on the nfc device
dev_down to turn off the nfc device

Signed-off-by: Ilan Elias <ilane@ti.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/nfc/pn533.c b/drivers/nfc/pn533.c
index f81a93e..c78eb6a 100644
--- a/drivers/nfc/pn533.c
+++ b/drivers/nfc/pn533.c
@@ -1432,6 +1432,8 @@
 }
 
 struct nfc_ops pn533_nfc_ops = {
+	.dev_up = NULL,
+	.dev_down = NULL,
 	.start_poll = pn533_start_poll,
 	.stop_poll = pn533_stop_poll,
 	.activate_target = pn533_activate_target,