ufs: ufs-qcom: Fix data corruption issue with FBE on F2FS

F2FS uses dun for data encryption/decryption via ICE. Hence,
allow the code to use it if a req has a dun. Without this there
will be data corruption issues when FBE is enabled on F2FS.

Change-Id: I02817c2a8a8f75f70e8a9b0988010a6a13ec1860
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>