Add guide to enable grub secure boot on ACRN.
Signed-off-by: Yonghua Huang <yonghua.huang@intel.com>
Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
Cleaned up the presentation and formatting problems from the conversion
to ReST, along with English grammar and spelling edits.
Signed-off-by: David B. Kinder <david.b.kinder@intel.com>