NFC: trf7970a: Cancel timer when error encountered

Some paths leave a timer still running when
trf7970a_send_err_upstream() is called.  This
can cause a timeout to occur in a subsequent
transaction making it fail.  Fix this by ensuring
there is no timer running before sending an error
upstream.
Signed-off-by: NMark A. Greer <mgreer@animalcreek.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

drivers/nfc/trf7970a.c

@@ -506,6 +506,8 @@ static void trf7970a_send_err_upstream(struct trf7970a *trf, int errno)
 {
 	dev_dbg(trf->dev, "Error - state: %d, errno: %d\n", trf->state, errno);
 
+	cancel_delayed_work(&trf->timeout_work);
+
 	kfree_skb(trf->rx_skb);
 	trf->rx_skb = ERR_PTR(errno);