Cleanup and and some missing overlays
camera: Restart preview after ZSL changes only if the preview is running

Don't touch the preview state if it was stopped to begin with

Change-Id: Ie81c01165778f98f92f11badc17c2023ea4610b7
Build libxml2.so

Needed by /system/bin/cnd

Change-Id: Ic47fd3082dd19020c076d16972288d62f830013e

Conflicts:
	g2.mk