serial: sh-sci: fix cannot work SH7723 SCIFA

SH7723 has SCIFA. This module is similer SCI register map, but it has FIFO.
So this patch adds new type(PORT_SCIFA) and change some type checking.

Signed-off-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>