Remove copying of TARGET_OUT_RAMDISK to recovery image

This was only needed for pushing first stage init to the recovery
image.  This isn't actually needed however, as the recovery image can
be fully shared and can run full init as long as there is a symlink
from /init to /system/bin/init, so that is added instead.

Bug: 80395578
Test: boot to recovery via this symlink
Change-Id: I8910543525a841401b209bfd98af30c5a0dc2688