change to default kernel which is 3.4

Change-Id: I14324f6db22c3499f49f86ae9ca1c3ccade71cc9
switch to ext4

Change-Id: I490f0d9f72b1d9e29de1e9628d4483fbf1875347
Merge tag 'android-4.4_r1' into kitkat-staging

Android 4.4 Release 1.0