Drop use of gce ramdisk.

This change disables gce ramdisk for good. Once this lands, we will be
booting up with Android ramdisk only.

BUG=65049764
Change-Id: Ie01ee39e4148ce8237aa09637f5b543cb77149cf

(cherry picked from commit 99725e9952fac925f488cb36863618219fc4ed0d)
3 files changed