Replace OTA keys when signing for A/B devices.

It replaces the package verification key (change of path due to
system_root_image flag), as well as the payload verification key.

Bug: 29397395
Change-Id: I10435072aaf4356f2d8b5e1b6e82eb9cead7ad62
(cherry picked from commit 24a72064309dd55d4aa80b70480eed55c54f818d)
1 file changed