crypto: hisilicon - Cap block size at 2^31

The function hisi_acc_create_sg_pool may allocate a block of
memory of size PAGE_SIZE * 2^(MAX_ORDER - 1).  This value may
exceed 2^31 on ia64, which would overflow the u32.

This patch caps it at 2^31.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: d8ac7b85 ("crypto: hisilicon - fix large sgl memory...")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>