Revert "FROMLIST: f2fs: fix use-after-free when accessing bio->bi_crypt_context"

This reverts commit ec877350.

This is a preparation change for merging android-5.4-stable.50
into msm-5.4 branch. Newer version of the imported change is
committed already as:

4c9af3eb f2fs: fix use-after-free when accessing bio->bi_crypt_context

Change-Id: Ie0ff68e50ad1cfe8a3a257b2d24e55a000bbe5c2
Signed-off-by: Blagovest Kolenichev <bkolenichev@codeaurora.org>