tty: serial: 8250: Fix type field in format string

The dev_dbg statement should print the value of uart.port.mapbase instead
of its address. Besides that, uart.port.irq and uart.port.iotype are all
unsigned types, so using %u is more appropriate.

Signed-off-by: Hao Lee <haolee.swjtu@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>