do not include dead code

This code has not been used for over 3yrs. Developers interested in its
origins, reference commit 4196e0fa5e0c6b2a27ee5626f4cfa22375ac6ea1 .

Change-Id: I588fa2fe4b92fa1508699a904d2be18b83b471c6
cleanup unused code

reset_ext4fs_info() is always called by make_ext4fs()

Change-Id: I48e75a7c55d21e4386bffa15d81aaeb702477df7
fix null struct exception

Change-Id: I9bf32849598c0725e2ce9a8a441bc41c6119c2bf
cleanup preserve data/media workaround

Change-Id: I634c9229368c6c8ea20cafb47c8c0403cae2be6c
Merge branch 'cm-11.0' of https://github.com/CyanogenMod/android_bootable_recovery into cm-11.0