staging: ccree: pick alloc mem flags based on req flags

The ccree driver was allocating memory using GFP_KERNEL flag
always, ignoring the flags set in the crypto request. Fix it
by choosing gfp flags based on crypto request flags.

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