OMAP: DSS2: DSI: fix use_sys_clk & highfreq

use_sys_clk and highfreq fields in dsi.current_cinfo were never set.
Luckily they weren't used anywhere so it didn't cause any problems.

This patch fixes those fields and they are now set at the same time as
the rest of the fields.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>