[POWERPC] CPM_UART: Fix non-console initialisation

The cpm_uart driver is initialised incorrectly, if there is a frame buffer
console, and CONFIG_SERIAL_CPM_CONSOLE is defined. The driver fails to
call cpm_uart_init_portdesc() and set_lineif() in this case.

Signed-off-by: Kalle Pokki <kalle.pokki@iki.fi>
Signed-off-by: Vitaly Bordug <vbordug@ru.mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>