[ARM] Fix 4417/1: Serial: Fix AMBA drivers locking

2389b272 contains a merge bug; fix it.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

drivers/serial/amba-pl010.c

@@ -167,9 +167,9 @@ static void pl010_rx_chars(struct uart_amba_port *uap)
 	ignore_char:
 		status = readb(uap->port.membase + UART01x_FR);
 	}
-	spin_unlock(&port->lock);
+	spin_unlock(&uap->port.lock);
 	tty_flip_buffer_push(tty);
-	spin_lock(&port->lock);
+	spin_lock(&uap->port.lock);
 }
 
 static void pl010_tx_chars(struct uart_amba_port *uap)