Sign recovery image

LK now requires recovery image to be signed. This
is a new change to ensure that only signed images
are used.

Change-Id: I25fef9c311370e3f26d2d09b577575cd2a16f880
Merge "Sign recovery image"
Merge ad35161d1c2e753e8cc33ba40e9b3405f50bf399 on remote branch

Change-Id: Ic959aa8baaa4a927bb3125c3882d0752943432b6
Merge "Merge ad35161d1c2e753e8cc33ba40e9b3405f50bf399 on remote branch"