Telephony: Fix incorrect status display on UI in airplane mode

UI should display "No Service" instead of "Searching for Service" in airplane
 mode. Changes done to set ERI text to "Searching for Service" only when
 radio is on.
 Ported from AOSP.
Change-Id: Ic7cc7b140c07103810789a17b21605903fb90541
Merge branch 'cm-11.0' of git://github.com/CyanogenMod/android_frameworks_opt_telephony into cm-11.0