scsi: ufs: Increase crypto thread priority

Crypto work is used to program file keys into
the Crypto HW. Some times the thread is scheduled
but is not executed and is preempted oftenly by
block i/o kworker. This causes same requests to be
requeued  leading to timeout and cpu overload issues.

Change-Id: Icd9b5108018b85d60d72858c92673e1f2feddbd4
Signed-off-by: Neeraj Soni <neersoni@codeaurora.org>