serial: bcm63xx_uart: don't use kfree() on non kmalloced area.

Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/serial/bcm63xx_uart.c b/drivers/serial/bcm63xx_uart.c
index 37ad0c4..f78ede8 100644
--- a/drivers/serial/bcm63xx_uart.c
+++ b/drivers/serial/bcm63xx_uart.c
@@ -830,7 +830,7 @@
 
 	ret = uart_add_one_port(&bcm_uart_driver, port);
 	if (ret) {
-		kfree(port);
+		ports[pdev->id].membase = 0;
 		return ret;
 	}
 	platform_set_drvdata(pdev, port);