Telephony: Add a config item to control fetching APN from OMH card

Change-Id: I5c14a6870ea0767cc14ff3addeeb0828cc704a32
CRs-Fixed: 748148
Signed-off-by: cj360 <ayunker551@gmail.com>

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