crypto: qcedev: Fix out of memory issue

Fixes memory leak issue which is caused due to unfreed memory
of req struct after processing the user space request, this
happens for every client who are using from user space through
ioctls.

Change-Id: I2f267b960a2c73a65b85e72b0bff9a87df68b4e0
Signed-off-by: AnilKumar Chimata <anilc@codeaurora.org>