crypto: testmgr - avoid DMA mapping from text, rodata, stack

With DMA_API_DEBUG set, following warnings are emitted
(tested on CAAM accelerator):
DMA-API: device driver maps memory from kernel text or rodata
DMA-API: device driver maps memory from stack
and the culprits are:
-key in __test_aead and __test_hash
-result in __test_hash

MAX_KEYLEN is changed to accommodate maximum key length from
existing test vectors in crypto/testmgr.h (131 bytes) and rounded.

Signed-off-by: Horia Geanta <horia.geanta@freescale.com>
Acked-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>