fb: set correct providers default value am/pm

fresh install shows am/pm on english timezones which
does not fit with the aosp default behaviour. Go inline with
it and hide it as default. User can change it then

Change-Id: I503818a16772f30260222ec5beed15e6654345a1
Merge remote-tracking branch 'upstream/kk4.4' into kk4.4