mmc: sdio_uart: remove meaningless BUG_ON

The code seems quite simple to maintain the sdio_uart_table,
and the insert/remove port from the table are symmetric. If
the BUG_ON occurs, which means serial_core modify the index
or mess up the port sequence anyway.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/card/sdio_uart.c

@@ -135,8 +135,6 @@ static void sdio_uart_port_remove(struct sdio_uart_port *port)
 {
 	struct sdio_func *func;
 
-	BUG_ON(sdio_uart_table[port->index] != port);
-
 	spin_lock(&sdio_uart_table_lock);
 	sdio_uart_table[port->index] = NULL;
 	spin_unlock(&sdio_uart_table_lock);