optimize build flags.

Change-Id: Ica7b29747a8e40e0f5c6eb5844a7963cdfc3f6e4
Don't need this here.

Change-Id: I570204c348eb4088c6d4d970725e97a39c6f8755
Update ramdisk.

Change-Id: Id255653cf25005c2be9287e4e68dcaf187f1992c