x86: Clean up ivybridge/chrome Kconfig options

There are some options which are never used, and also some options
which are selected by others but have never been a Kconfg option.
Clean these up.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>