init: swap to using fs_mgr for mount/checks

Change-Id: Ie1466e2331cfcc04af5870fb39696f5a873fabda
Merge branch 'jb-mr1' of git://github.com/KFire-Android/android_device_amazon_otter into cm-10.1
Merge remote-tracking branch 'origin/cm-10.1' into cm-10.1