Default back to LTE/WCDMA/GSM if supported

Currently after unchecking the 'Use only 2G networks' option, the
default Network Mode is 'WCDMA Preferred'.  This patch will change
the behaviour so that if the mobiel supports LTE, the default mode
upon unchecking 'Use only 2G networks' is LTE/WCDMA/GSM

Change-Id: I80be0eee564aa76e5cd978595bff98eb461e00f7