cbgfx: Add portrait screen support

cbgfx currently does not support portrait screen which height >width.
so add it.

Change-Id: I66fee6d73654e736a2db4a3d191f030c52a23e0d
Signed-off-by: Nickey Yang <nickey.yang@rock-chips.com>
Reviewed-on: https://review.coreboot.org/19474
Tested-by: build bot (Jenkins)
Reviewed-by: Julius Werner <jwerner@chromium.org>
1 file changed