rockchip: ram: sdram_rk3x88: replace comma by semicolon

A comma at the end of a line gives sometimes strange
effects in combination with some code formatters,
so replace a comma by a semicolon in the sdram_rk3188.c
and sdram_rk3288.c files.

Signed-off-by: Johan Jonker <jbx6244@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>