Set cpu variant to krait

Change-Id: Ie64b994e2b399b735afbf58b43b86b9b11543bb0
proprietary-files: Add libdrmdecrypt

Change-Id: Ic7bdf11edec90a5ca19fbcbd15690e8d53015d31
proprietary-files: add rfs_access

Change-Id: I39f0e3260d262ddfa0ceca463b033aa123286fc9
rootfs: Align with Moto and caf

Change-Id: Ibc211097aa45e88184b8eb395a7ae4b30a4f9cb7