PackageManager: allow build-time disabling of components

Allow components to be specified as disabled at build time
(applied on boot).

This allows stock OTA components to be marked as disabled in
DU builds.

Conflicts:
	core/res/res/values/config.xml
	core/res/res/values/symbols.xml

Change-Id: I6e4499cc40a779792a5ea97a10137399dad7d69f