Add secureboot signed container to gitignore
Add secureboot signed container to gitignore

Change-Id: Id1dfa070d54c839aa1880064fa864b2ad55c74c3
ForwardPort: yes
Reviewed-on: http://ralgit01.raleigh.ibm.com/gerrit1/24980
Tested-by: Jenkins Server
Tested-by: FSP CI Jenkins
Reviewed-by: William G. Hoffa <7dd6aa5e78423995d9d7c7ecada5b77ee07f88cc@us.ibm.com>

Over-enthusiastic/hostboot,Over-enthusiastic/hostboot,Over-enthusiastic/hostboot,Over-enthusiastic/hostboot,Over-enthusiastic/hostboot