staging: ccree: copy larval digest from RAM

The ccree driver was using a DMA operation to copy larval digest
from the ccree SRAM to RAM. Replace it with a simple memcpy.

Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>