ls990: bring up overlays

* add eri.xml
* add config.xml
* update carrier props
* add sprint overlays for frameworks and mms app

Change-Id: Icd9cc587451d5d31aab91c5b9c52883bfb9cb48f

Conflicts:
	overlay/frameworks/base/core/res/res/values/config.xml
	overlay/frameworks/base/core/res/res/xml/eri.xml
	system.prop