m7: f2fs Upstream Update.

Squashed commit from https://github.com/CyanogenMod/android_kernel_htc_m7/commits/cm-11.0
The commits between
1. https://github.com/CyanogenMod/android_kernel_htc_m7/commit/ad9a4fa2d2839b4504366ae208123738077325e0
and
2. https://github.com/CyanogenMod/android_kernel_htc_m7/commit/d110df41d3b7e61bb93107d85c2447e061e850aa

were included..

Change-Id: Ia68803e8a375650201fe547eabd5968dd9eef7f1