uboot-imx

serial: sh: Change definition of clock of SCIF

The former SH/SCIF driver had calculated baudrate based on CONFIG_SYS_CLK_FREQ.
The newest SH/SCIF needs calculation of the clock for SCIF.
This patch defines clock CONFIG_SH_SCIF_CLK_FREQ for SCIF and changes it to
CONFIG_SH_SCIF_CLK_FREQ from CONFIG_SYS_CLK_FREQ.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
CC: Albert Aribaud <albert.u.boot@aribaud.net>